tor-browser

BrowserChild.cpp (156483B)

---

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "BrowserChild.h"

#ifdef ACCESSIBILITY
#  include "mozilla/a11y/DocAccessibleChild.h"
#endif
#include <utility>

#include "BrowserParent.h"
#include "ContentChild.h"
#include "EventStateManager.h"
#include "MMPrinter.h"
#include "PuppetWidget.h"
#include "StructuredCloneData.h"
#include "UnitTransforms.h"
#include "Units.h"
#include "VRManagerChild.h"
#include "mozilla/Assertions.h"
#include "mozilla/BasePrincipal.h"
#include "mozilla/EventForwards.h"
#include "mozilla/EventListenerManager.h"
#include "mozilla/HoldDropJSObjects.h"
#include "mozilla/IMEStateManager.h"
#include "mozilla/LookAndFeel.h"
#include "mozilla/MediaFeatureChange.h"
#include "mozilla/MiscEvents.h"
#include "mozilla/MouseEvents.h"
#include "mozilla/NativeKeyBindingsType.h"
#include "mozilla/NullPrincipal.h"
#include "mozilla/PointerLockManager.h"
#include "mozilla/PresShell.h"
#include "mozilla/ProcessHangMonitor.h"
#include "mozilla/ProfilerLabels.h"
#include "mozilla/SchedulerGroup.h"
#include "mozilla/ScopeExit.h"
#include "mozilla/Services.h"
#include "mozilla/StaticPrefs_dom.h"
#include "mozilla/TextEvents.h"
#include "mozilla/ToString.h"
#include "mozilla/dom/AutoPrintEventDispatcher.h"
#include "mozilla/dom/BrowserBridgeChild.h"
#include "mozilla/dom/DataTransfer.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/Event.h"
#include "mozilla/dom/ImageDocument.h"
#include "mozilla/dom/JSWindowActorChild.h"
#include "mozilla/dom/LoadURIOptionsBinding.h"
#include "mozilla/dom/MessageManagerBinding.h"
#include "mozilla/dom/MouseEventBinding.h"
#include "mozilla/dom/Nullable.h"
#include "mozilla/dom/PBrowser.h"
#include "mozilla/dom/PaymentRequestChild.h"
#include "mozilla/dom/PointerEventHandler.h"
#include "mozilla/dom/SessionStoreChild.h"
#include "mozilla/dom/SessionStoreUtils.h"
#include "mozilla/dom/UserActivation.h"
#include "mozilla/dom/ViewTransition.h"
#include "mozilla/dom/WindowGlobalChild.h"
#include "mozilla/dom/WindowProxyHolder.h"
#include "mozilla/gfx/CrossProcessPaint.h"
#include "mozilla/gfx/Matrix.h"
#include "mozilla/ipc/BackgroundChild.h"
#include "mozilla/ipc/BackgroundUtils.h"
#include "mozilla/ipc/PBackgroundChild.h"
#include "mozilla/layers/APZCCallbackHelper.h"
#include "mozilla/layers/APZCTreeManagerChild.h"
#include "mozilla/layers/APZChild.h"
#include "mozilla/layers/APZEventState.h"
#include "mozilla/layers/CompositorBridgeChild.h"
#include "mozilla/layers/ContentProcessController.h"
#include "mozilla/layers/DoubleTapToZoom.h"
#include "mozilla/layers/IAPZCTreeManager.h"
#include "mozilla/layers/ImageBridgeChild.h"
#include "mozilla/layers/InputAPZContext.h"
#include "mozilla/layers/TouchActionHelper.h"
#include "mozilla/layers/WebRenderLayerManager.h"
#include "mozilla/widget/ScreenManager.h"
#include "mozilla/widget/WidgetLogging.h"
#include "nsCommandParams.h"
#include "nsContentPermissionHelper.h"
#include "nsContentUtils.h"
#include "nsDeviceContext.h"
#include "nsDocShell.h"
#include "nsDocShellLoadState.h"
#include "nsDragServiceProxy.h"
#include "nsExceptionHandler.h"
#include "nsFilePickerProxy.h"
#include "nsFocusManager.h"
#include "nsGlobalWindowOuter.h"
#include "nsIBaseWindow.h"
#include "nsIBrowserDOMWindow.h"
#include "nsIClassifiedChannel.h"
#include "nsIDocShell.h"
#include "nsIFrame.h"
#include "nsILoadContext.h"
#include "nsIOpenWindowInfo.h"
#include "nsISHEntry.h"
#include "nsISHistory.h"
#include "nsIScreenManager.h"
#include "nsIScriptError.h"
#include "nsIURI.h"
#include "nsIURIMutator.h"
#include "nsIWeakReferenceUtils.h"
#include "nsIWebBrowser.h"
#include "nsIWebProgress.h"
#include "nsIXULRuntime.h"
#include "nsLayoutUtils.h"
#include "nsNetUtil.h"
#include "nsPIDOMWindow.h"
#include "nsPIWindowRoot.h"
#include "nsPrintfCString.h"
#include "nsRefreshDriver.h"
#include "nsThreadManager.h"
#include "nsThreadUtils.h"
#include "nsVariant.h"
#include "nsWebBrowser.h"
#include "nsWindowWatcher.h"

#ifdef MOZ_WAYLAND
#  include "nsAppRunner.h"
#endif

#ifdef NS_PRINTING
#  include "mozilla/layout/RemotePrintJobChild.h"
#  include "nsIPrintSettings.h"
#  include "nsIPrintSettingsService.h"
#  include "nsIWebBrowserPrint.h"
#endif

static mozilla::LazyLogModule sApzChildLog("apz.child");

using namespace mozilla;
using namespace mozilla::dom;
using namespace mozilla::dom::ipc;
using namespace mozilla::ipc;
using namespace mozilla::layers;
using namespace mozilla::layout;
using namespace mozilla::widget;
using mozilla::layers::GeckoContentController;

static const char BEFORE_FIRST_PAINT[] = "before-first-paint";

static uint32_t sConsecutiveTouchMoveCount = 0;

using BrowserChildMap = nsTHashMap<nsUint64HashKey, BrowserChild*>;
static BrowserChildMap* sBrowserChildren;
StaticMutex sBrowserChildrenMutex;

namespace {

class SynthesizedEventChildCallback final : public nsISynthesizedEventCallback {
 NS_DECL_ISUPPORTS

public:
 SynthesizedEventChildCallback(BrowserChild* aBrowserChild,
                               const uint64_t& aCallbackId)
     : mBrowserChild(aBrowserChild), mCallbackId(aCallbackId) {
   MOZ_ASSERT(mBrowserChild);
   MOZ_ASSERT(mCallbackId > 0, "Invalid callback ID");
 }

 NS_IMETHOD OnCompleteDispatch() override {
   MOZ_ASSERT(mCallbackId > 0, "Invalid callback ID");

   if (!mBrowserChild) {
     // We already sent the notification, or we don't actually need to
     // send any notification at all.
     MOZ_ASSERT_UNREACHABLE("OnCompleteDispatch called multiple times");
     return NS_OK;
   }

   if (mBrowserChild->IsDestroyed()) {
     // If this happens it's probably a bug in the test that's triggering this.
     NS_WARNING(
         "BrowserChild was unexpectedly destroyed during event "
         "synthesization response!");
   } else if (!mBrowserChild->SendSynthesizedEventResponse(mCallbackId)) {
     NS_WARNING("Unable to send event synthesization response!");
   }
   // Null out browserChild to indicate we already sent the response
   mBrowserChild = nullptr;
   return NS_OK;
 }

private:
 virtual ~SynthesizedEventChildCallback() = default;

 RefPtr<BrowserChild> mBrowserChild;
 uint64_t mCallbackId;
};

NS_IMPL_ISUPPORTS(SynthesizedEventChildCallback, nsISynthesizedEventCallback)

template <class T>
class MOZ_RAII AutoSynthesizedEventResponder final {
public:
 AutoSynthesizedEventResponder(BrowserChild* aBrowserChild, const T& aEvent) {
   if (aEvent.mCallbackId.isSome()) {
     mCallback = MakeAndAddRef<SynthesizedEventChildCallback>(
         aBrowserChild, aEvent.mCallbackId.ref());
   }
 }

 ~AutoSynthesizedEventResponder() {
   if (mCallback) {
     mCallback->OnCompleteDispatch();
   }
 }

private:
 nsCOMPtr<nsISynthesizedEventCallback> mCallback;
};

}  // namespace

already_AddRefed<Document> BrowserChild::GetTopLevelDocument() const {
 nsCOMPtr<nsIDocShell> docShell = do_GetInterface(WebNavigation());
 nsCOMPtr<Document> doc = docShell ? docShell->GetExtantDocument() : nullptr;
 return doc.forget();
}

PresShell* BrowserChild::GetTopLevelPresShell() const {
 if (RefPtr<Document> doc = GetTopLevelDocument()) {
   return doc->GetPresShell();
 }
 return nullptr;
}

bool BrowserChild::UpdateFrame(const RepaintRequest& aRequest) {
 MOZ_ASSERT(aRequest.GetScrollId() != ScrollableLayerGuid::NULL_SCROLL_ID);

 if (aRequest.IsRootContent()) {
   if (PresShell* presShell = GetTopLevelPresShell()) {
     // Guard against stale updates (updates meant for a pres shell which
     // has since been torn down and destroyed).
     if (aRequest.GetPresShellId() == presShell->GetPresShellId()) {
       APZCCallbackHelper::UpdateRootFrame(aRequest);
       return true;
     }
   }
 } else {
   // aRequest.mIsRoot is false, so we are trying to update a subframe.
   // This requires special handling.
   APZCCallbackHelper::UpdateSubFrame(aRequest);
   return true;
 }
 return true;
}

class BrowserChild::DelayedDeleteRunnable final : public Runnable,
                                                 public nsIRunnablePriority {
 RefPtr<BrowserChild> mBrowserChild;

 // In order to try that this runnable runs after everything that could
 // possibly touch this tab, we send it through the event queue twice.
 bool mReadyToDelete = false;

public:
 explicit DelayedDeleteRunnable(BrowserChild* aBrowserChild)
     : Runnable("BrowserChild::DelayedDeleteRunnable"),
       mBrowserChild(aBrowserChild) {
   MOZ_ASSERT(NS_IsMainThread());
   MOZ_ASSERT(aBrowserChild);
 }

 NS_DECL_ISUPPORTS_INHERITED

private:
 ~DelayedDeleteRunnable() {
   MOZ_ASSERT(NS_IsMainThread());
   MOZ_ASSERT(!mBrowserChild);
 }

 NS_IMETHOD GetPriority(uint32_t* aPriority) override {
   *aPriority = nsIRunnablePriority::PRIORITY_NORMAL;
   return NS_OK;
 }

 NS_IMETHOD
 Run() override {
   MOZ_ASSERT(NS_IsMainThread());
   MOZ_ASSERT(mBrowserChild);

   if (!mReadyToDelete) {
     // This time run this runnable at input priority.
     mReadyToDelete = true;
     MOZ_ALWAYS_SUCCEEDS(NS_DispatchToCurrentThread(this));
     return NS_OK;
   }

   // Check in case ActorDestroy was called after RecvDestroy message.
   if (mBrowserChild->IPCOpen()) {
     (void)PBrowserChild::Send__delete__(mBrowserChild);
   }

   mBrowserChild = nullptr;
   return NS_OK;
 }
};

NS_IMPL_ISUPPORTS_INHERITED(BrowserChild::DelayedDeleteRunnable, Runnable,
                           nsIRunnablePriority)

namespace {
std::map<TabId, RefPtr<BrowserChild>>& NestedBrowserChildMap() {
 MOZ_ASSERT(NS_IsMainThread());
 static std::map<TabId, RefPtr<BrowserChild>> sNestedBrowserChildMap;
 return sNestedBrowserChildMap;
}
}  // namespace

already_AddRefed<BrowserChild> BrowserChild::FindBrowserChild(
   const TabId& aTabId) {
 auto iter = NestedBrowserChildMap().find(aTabId);
 if (iter == NestedBrowserChildMap().end()) {
   return nullptr;
 }
 RefPtr<BrowserChild> browserChild = iter->second;
 return browserChild.forget();
}

/*static*/
already_AddRefed<BrowserChild> BrowserChild::Create(
   ContentChild* aManager, const TabId& aTabId, const TabContext& aContext,
   BrowsingContext* aBrowsingContext, uint32_t aChromeFlags,
   bool aIsTopLevel) {
 RefPtr<BrowserChild> iframe = new BrowserChild(
     aManager, aTabId, aContext, aBrowsingContext, aChromeFlags, aIsTopLevel);
 return iframe.forget();
}

BrowserChild::BrowserChild(ContentChild* aManager, const TabId& aTabId,
                          const TabContext& aContext,
                          BrowsingContext* aBrowsingContext,
                          uint32_t aChromeFlags, bool aIsTopLevel)
   : TabContext(aContext),
     mBrowserChildMessageManager(nullptr),
     mManager(aManager),
     mBrowsingContext(aBrowsingContext),
     mChromeFlags(aChromeFlags),
     mMaxTouchPoints(0),
     mLayersId{0},
     mEffectsInfo{EffectsInfo::FullyHidden()},
     mDynamicToolbarMaxHeight(0),
     mKeyboardHeight(0),
     mUniqueId(aTabId),
     mDidFakeShow(false),
     mTriedBrowserInit(false),
     mHasValidInnerSize(false),
     mDestroyed(false),
     mInAndroidPipMode(false),
     mIsTopLevel(aIsTopLevel),
     mIsTransparent(false),
     mIPCOpen(false),
     mDidSetRealShowInfo(false),
     mDidLoadURLInit(false),
     mSkipKeyPress(false),
     mShouldSendWebProgressEventsToParent(false),
     mRenderLayers(true),
     mIsPreservingLayers(false),
#if defined(XP_WIN) && defined(ACCESSIBILITY)
     mNativeWindowHandle(0),
#endif
     mCancelContentJSEpoch(0) {
 mozilla::HoldJSObjects(this);

 // preloaded BrowserChild should not be added to child map
 if (mUniqueId) {
   MOZ_ASSERT(NestedBrowserChildMap().find(mUniqueId) ==
              NestedBrowserChildMap().end());
   NestedBrowserChildMap()[mUniqueId] = this;
 }
 mCoalesceMouseMoveEvents = StaticPrefs::dom_events_coalesce_mousemove();
 if (mCoalesceMouseMoveEvents) {
   mCoalescedMouseEventFlusher = new CoalescedMouseMoveFlusher(this);
 }

 if (StaticPrefs::dom_events_coalesce_touchmove()) {
   mCoalescedTouchMoveEventFlusher = new CoalescedTouchMoveFlusher(this);
 }
}

const CompositorOptions& BrowserChild::GetCompositorOptions() const {
 // If you're calling this before mCompositorOptions is set, well.. don't.
 MOZ_ASSERT(mCompositorOptions);
 return mCompositorOptions.ref();
}

bool BrowserChild::AsyncPanZoomEnabled() const {
 // This might get called by the TouchEvent::PrefEnabled code before we have
 // mCompositorOptions populated (bug 1370089). In that case we just assume
 // APZ is enabled because we're in a content process (because BrowserChild)
 // and APZ is probably going to be enabled here since e10s is enabled.
 return mCompositorOptions ? mCompositorOptions->UseAPZ() : true;
}

NS_IMETHODIMP
BrowserChild::Observe(nsISupports* aSubject, const char* aTopic,
                     const char16_t* aData) {
 if (!strcmp(aTopic, BEFORE_FIRST_PAINT)) {
   if (AsyncPanZoomEnabled()) {
     nsCOMPtr<Document> subject(do_QueryInterface(aSubject));
     nsCOMPtr<Document> doc(GetTopLevelDocument());

     if (subject == doc) {
       RefPtr<PresShell> presShell = doc->GetPresShell();
       if (presShell) {
         presShell->SetIsFirstPaint(true);
       }

       APZCCallbackHelper::InitializeRootDisplayport(presShell);
     }
   }
 }

 return NS_OK;
}

void BrowserChild::ContentReceivedInputBlock(uint64_t aInputBlockId,
                                            bool aPreventDefault) const {
 if (mApzcTreeManager) {
   mApzcTreeManager->ContentReceivedInputBlock(aInputBlockId, aPreventDefault);
 }
}

void BrowserChild::SetTargetAPZC(
   uint64_t aInputBlockId,
   const nsTArray<ScrollableLayerGuid>& aTargets) const {
 if (mApzcTreeManager) {
   mApzcTreeManager->SetTargetAPZC(aInputBlockId, aTargets);
 }
}

bool BrowserChild::DoUpdateZoomConstraints(
   const uint32_t& aPresShellId, const ViewID& aViewId,
   const Maybe<ZoomConstraints>& aConstraints) {
 if (!mApzcTreeManager || mDestroyed) {
   return false;
 }

 ScrollableLayerGuid guid =
     ScrollableLayerGuid(mLayersId, aPresShellId, aViewId);

 mApzcTreeManager->UpdateZoomConstraints(guid, aConstraints);
 return true;
}

nsresult BrowserChild::Init(mozIDOMWindowProxy* aParent,
                           WindowGlobalChild* aInitialWindowChild,
                           nsIOpenWindowInfo* aOpenWindowInfo) {
 MOZ_ASSERT(aOpenWindowInfo, "Must have openwindowinfo");
 MOZ_ASSERT(aInitialWindowChild, "Must have window child");
 MOZ_ASSERT(aInitialWindowChild->BrowsingContext() == mBrowsingContext);
 MOZ_ASSERT(aInitialWindowChild->DocumentPrincipal() ==
            aOpenWindowInfo->PrincipalToInheritForAboutBlank());

 nsCOMPtr<nsIWidget> widget = nsIWidget::CreatePuppetWidget(this);
 mPuppetWidget = static_cast<PuppetWidget*>(widget.get());
 if (!mPuppetWidget) {
   NS_ERROR("couldn't create fake widget");
   return NS_ERROR_FAILURE;
 }
 mPuppetWidget->InfallibleCreate(nullptr, LayoutDeviceIntRect(),
                                 widget::InitData());

 mWebBrowser = nsWebBrowser::Create(this, mPuppetWidget, mBrowsingContext,
                                    aInitialWindowChild, aOpenWindowInfo);
 if (!mWebBrowser) {
   // At least the JS recursion depth check can cause an early return
   // here. dom/base/crashtests/1419902.html
   return NS_ERROR_FAILURE;
 }
 nsIWebBrowser* webBrowser = mWebBrowser;

 mWebNav = do_QueryInterface(webBrowser);
 NS_ASSERTION(mWebNav, "nsWebBrowser doesn't implement nsIWebNavigation?");

 // IPC uses a WebBrowser object for which DNS prefetching is turned off
 // by default. But here we really want it, so enable it explicitly
 mWebBrowser->SetAllowDNSPrefetch(true);

 nsCOMPtr<nsIDocShell> docShell = do_GetInterface(WebNavigation());
 MOZ_ASSERT(docShell);

#ifdef DEBUG
 nsCOMPtr<nsILoadContext> loadContext = do_GetInterface(WebNavigation());
 MOZ_ASSERT(loadContext);
 MOZ_ASSERT(loadContext->UseRemoteTabs() ==
            !!(mChromeFlags & nsIWebBrowserChrome::CHROME_REMOTE_WINDOW));
 MOZ_ASSERT(loadContext->UseRemoteSubframes() ==
            !!(mChromeFlags & nsIWebBrowserChrome::CHROME_FISSION_WINDOW));
#endif  // defined(DEBUG)

 // Few lines before, baseWindow->Create() will end up creating a new
 // window root in nsGlobalWindowOuter::SetDocShell.
 // Then this chrome event handler, will be inherited to inner windows.
 // We want to also set it to the docshell so that inner windows
 // and any code that has access to the docshell
 // can all listen to the same chrome event handler.
 // XXX: ideally, we would set a chrome event handler earlier,
 // and all windows, even the root one, will use the docshell one.
 nsCOMPtr<nsPIDOMWindowOuter> window = do_GetInterface(WebNavigation());
 NS_ENSURE_TRUE(window, NS_ERROR_FAILURE);
 nsCOMPtr<EventTarget> chromeHandler = window->GetChromeEventHandler();
 docShell->SetChromeEventHandler(chromeHandler);

 // Window scrollbar flags only affect top level remote frames, not fission
 // frames.
 if (mIsTopLevel) {
   nsContentUtils::SetScrollbarsVisibility(
       docShell, !!(mChromeFlags & nsIWebBrowserChrome::CHROME_SCROLLBARS));
 }

 nsWeakPtr weakPtrThis = do_GetWeakReference(
     static_cast<nsIBrowserChild*>(this));  // for capture by the lambda
 ContentReceivedInputBlockCallback callback(
     [weakPtrThis](uint64_t aInputBlockId, bool aPreventDefault) {
       if (nsCOMPtr<nsIBrowserChild> browserChild =
               do_QueryReferent(weakPtrThis)) {
         static_cast<BrowserChild*>(browserChild.get())
             ->ContentReceivedInputBlock(aInputBlockId, aPreventDefault);
       }
     });
 mAPZEventState = new APZEventState(mPuppetWidget, std::move(callback));

 mIPCOpen = true;

 if (SessionStorePlatformCollection()) {
   mSessionStoreChild = SessionStoreChild::GetOrCreate(mBrowsingContext);
 }

 // We've all set up, make sure our visibility state is consistent. This is
 // important for OOP iframes, which start off as hidden.
 UpdateVisibility();

 return NS_OK;
}

NS_IMPL_CYCLE_COLLECTION_CLASS(BrowserChild)

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(BrowserChild)
 NS_IMPL_CYCLE_COLLECTION_UNLINK(mBrowserChildMessageManager)
 tmp->nsMessageManagerScriptExecutor::Unlink();
 NS_IMPL_CYCLE_COLLECTION_UNLINK(mWebBrowser)
 NS_IMPL_CYCLE_COLLECTION_UNLINK(mWebNav)
 NS_IMPL_CYCLE_COLLECTION_UNLINK(mBrowsingContext)
 NS_IMPL_CYCLE_COLLECTION_UNLINK(mSessionStoreChild)
 NS_IMPL_CYCLE_COLLECTION_UNLINK(mContentTransformPromise)
 NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_REFERENCE
NS_IMPL_CYCLE_COLLECTION_UNLINK_END

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(BrowserChild)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mBrowserChildMessageManager)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mWebBrowser)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mWebNav)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mBrowsingContext)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mSessionStoreChild)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mContentTransformPromise)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(BrowserChild)
 tmp->nsMessageManagerScriptExecutor::Trace(aCallbacks, aClosure);
NS_IMPL_CYCLE_COLLECTION_TRACE_END

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(BrowserChild)
 NS_INTERFACE_MAP_ENTRY_CONCRETE(BrowserChild)
 NS_INTERFACE_MAP_ENTRY(nsIWebBrowserChrome)
 NS_INTERFACE_MAP_ENTRY(nsIInterfaceRequestor)
 NS_INTERFACE_MAP_ENTRY(nsIWindowProvider)
 NS_INTERFACE_MAP_ENTRY(nsIBrowserChild)
 NS_INTERFACE_MAP_ENTRY(nsIObserver)
 NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
 NS_INTERFACE_MAP_ENTRY(nsITooltipListener)
 NS_INTERFACE_MAP_ENTRY(nsIWebProgressListener)
 NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIBrowserChild)
NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTING_ADDREF(BrowserChild)
NS_IMPL_CYCLE_COLLECTING_RELEASE(BrowserChild)

NS_IMETHODIMP
BrowserChild::GetChromeFlags(uint32_t* aChromeFlags) {
 *aChromeFlags = mChromeFlags;
 return NS_OK;
}

NS_IMETHODIMP
BrowserChild::SetChromeFlags(uint32_t aChromeFlags) {
 NS_WARNING("trying to SetChromeFlags from content process?");

 return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
BrowserChild::RemoteDropLinks(
   const nsTArray<RefPtr<nsIDroppedLinkItem>>& aLinks) {
 nsTArray<nsString> linksArray;
 nsresult rv = NS_OK;
 for (nsIDroppedLinkItem* link : aLinks) {
   nsString tmp;
   rv = link->GetUrl(tmp);
   if (NS_FAILED(rv)) {
     return rv;
   }
   linksArray.AppendElement(tmp);

   rv = link->GetName(tmp);
   if (NS_FAILED(rv)) {
     return rv;
   }
   linksArray.AppendElement(tmp);

   rv = link->GetType(tmp);
   if (NS_FAILED(rv)) {
     return rv;
   }
   linksArray.AppendElement(tmp);
 }
 bool sent = SendDropLinks(linksArray);

 return sent ? NS_OK : NS_ERROR_FAILURE;
}

NS_IMETHODIMP
BrowserChild::ShowAsModal() {
 NS_WARNING("BrowserChild::ShowAsModal not supported in BrowserChild");

 return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
BrowserChild::IsWindowModal(bool* aRetVal) {
 *aRetVal = false;
 return NS_OK;
}

NS_IMETHODIMP
BrowserChild::SetLinkStatus(const nsAString& aStatusText) {
 // We can only send the status after the ipc machinery is set up
 if (IPCOpen()) {
   SendSetLinkStatus(aStatusText);
 }
 return NS_OK;
}

NS_IMETHODIMP
BrowserChild::SetDimensions(DimensionRequest&& aRequest) {
 // The parent is in charge of the dimension changes. If JS code wants to
 // change the dimensions (moveTo, screenX, etc.) we send a message to the
 // parent about the new requested dimension, the parent does the resize/move
 // then send a message to the child to update itself. For APIs like screenX
 // this function is called with only the changed values.  In a series of calls
 // like window.screenX = 10; window.screenY = 10; for the second call, since
 // screenX is not yet updated we might accidentally reset back screenX to it's
 // old value. To avoid this, if a parameter did not change, we want the parent
 // to handle the unchanged values.

 double scale = mPuppetWidget ? mPuppetWidget->GetDefaultScale().scale : 1.0;
 SendSetDimensions(aRequest, scale);
 return NS_OK;
}

NS_IMETHODIMP
BrowserChild::GetDimensions(DimensionKind aDimensionKind, int32_t* aX,
                           int32_t* aY, int32_t* aCx, int32_t* aCy) {
 LayoutDeviceIntRect rect = GetOuterRect();
 if (aDimensionKind == DimensionKind::Inner) {
   if (aX || aY) {
     return NS_ERROR_NOT_IMPLEMENTED;
   }
   rect.SizeTo(GetInnerSize());
 }
 if (aX) {
   *aX = rect.x;
 }
 if (aY) {
   *aY = rect.y;
 }
 if (aCx) {
   *aCx = rect.width;
 }
 if (aCy) {
   *aCy = rect.height;
 }
 return NS_OK;
}

NS_IMETHODIMP
BrowserChild::Blur() { return NS_ERROR_NOT_IMPLEMENTED; }

NS_IMETHODIMP
BrowserChild::GetInterface(const nsIID& aIID, void** aSink) {
 // XXXbz should we restrict the set of interfaces we hand out here?
 // See bug 537429
 return QueryInterface(aIID, aSink);
}

NS_IMETHODIMP
BrowserChild::ProvideWindow(nsIOpenWindowInfo* aOpenWindowInfo,
                           uint32_t aChromeFlags, bool aCalledFromJS,
                           nsIURI* aURI, const nsAString& aName,
                           const nsACString& aFeatures,
                           const UserActivation::Modifiers& aModifiers,
                           bool aForceNoOpener, bool aForceNoReferrer,
                           bool aIsPopupRequested,
                           nsDocShellLoadState* aLoadState, bool* aWindowIsNew,
                           BrowsingContext** aReturn) {
 *aReturn = nullptr;

 RefPtr<BrowsingContext> parent = aOpenWindowInfo->GetParent();

 int32_t openLocation = nsWindowWatcher::GetWindowOpenLocation(
     parent->GetDOMWindow(), aChromeFlags, aModifiers, aCalledFromJS,
     aOpenWindowInfo->GetIsForPrinting());

 // If it turns out we're opening in the current browser, just hand over the
 // current browser's docshell.
 if (openLocation == nsIBrowserDOMWindow::OPEN_CURRENTWINDOW) {
   nsCOMPtr<nsIWebBrowser> browser = do_GetInterface(WebNavigation());
   *aWindowIsNew = false;

   nsCOMPtr<mozIDOMWindowProxy> win;
   MOZ_TRY(browser->GetContentDOMWindow(getter_AddRefs(win)));

   RefPtr<BrowsingContext> bc(
       nsPIDOMWindowOuter::From(win)->GetBrowsingContext());
   bc.forget(aReturn);
   return NS_OK;
 }

 // Note that ProvideWindowCommon may return NS_ERROR_ABORT if the
 // open window call was canceled.  It's important that we pass this error
 // code back to our caller.
 ContentChild* cc = ContentChild::GetSingleton();
 return cc->ProvideWindowCommon(
     WrapNotNull(this), aOpenWindowInfo, aChromeFlags, aCalledFromJS, aURI,
     aName, aFeatures, aModifiers, aForceNoOpener, aForceNoReferrer,
     aIsPopupRequested, aLoadState, aWindowIsNew, aReturn);
}

void BrowserChild::DestroyWindow() {
 mBrowsingContext = nullptr;

 if (mCoalescedMouseEventFlusher) {
   mCoalescedMouseEventFlusher->RemoveObserver();
   mCoalescedMouseEventFlusher = nullptr;
 }

 if (mCoalescedTouchMoveEventFlusher) {
   mCoalescedTouchMoveEventFlusher->RemoveObserver();
   mCoalescedTouchMoveEventFlusher = nullptr;
 }

 if (mSessionStoreChild) {
   mSessionStoreChild->Stop();
   mSessionStoreChild = nullptr;
 }

 // In case we don't have chance to process all entries, clean all data in
 // the queue.
 while (mToBeDispatchedMouseData.GetSize() > 0) {
   UniquePtr<CoalescedMouseData> data(
       static_cast<CoalescedMouseData*>(mToBeDispatchedMouseData.PopFront()));
   data.reset();
 }

 nsCOMPtr<nsIBaseWindow> baseWindow = do_QueryInterface(WebNavigation());
 if (baseWindow) baseWindow->Destroy();

 if (mPuppetWidget) {
   mPuppetWidget->Destroy();
 }

 mLayersConnected = Nothing();

 if (mLayersId.IsValid()) {
   StaticMutexAutoLock lock(sBrowserChildrenMutex);

   MOZ_ASSERT(sBrowserChildren);
   sBrowserChildren->Remove(uint64_t(mLayersId));
   if (!sBrowserChildren->Count()) {
     delete sBrowserChildren;
     sBrowserChildren = nullptr;
   }
   mLayersId = layers::LayersId{0};
 }

 if (mAPZEventState) {
   mAPZEventState->Destroy();
   mAPZEventState = nullptr;
 }
}

void BrowserChild::ActorDestroy(ActorDestroyReason why) {
 mIPCOpen = false;

 DestroyWindow();

 if (mBrowserChildMessageManager) {
   // We should have a message manager if the global is alive, but it
   // seems sometimes we don't.  Assert in aurora/nightly, but don't
   // crash in release builds.
   MOZ_DIAGNOSTIC_ASSERT(mBrowserChildMessageManager->GetMessageManager());
   if (mBrowserChildMessageManager->GetMessageManager()) {
     // The messageManager relays messages via the BrowserChild which
     // no longer exists.
     mBrowserChildMessageManager->DisconnectMessageManager();
   }
 }

 if (GetTabId() != 0) {
   NestedBrowserChildMap().erase(GetTabId());
 }
}

BrowserChild::~BrowserChild() {
 mAnonymousGlobalScopes.Clear();

 DestroyWindow();

 nsCOMPtr<nsIWebBrowser> webBrowser = do_QueryInterface(WebNavigation());
 if (webBrowser) {
   webBrowser->SetContainerWindow(nullptr);
 }

 mozilla::DropJSObjects(this);
}

mozilla::ipc::IPCResult BrowserChild::RecvWillChangeProcess() {
 if (mWebBrowser) {
   mWebBrowser->SetWillChangeProcess();
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvLoadURL(
   nsDocShellLoadState* aLoadState, const ParentShowInfo& aInfo) {
 if (!mDidLoadURLInit) {
   mDidLoadURLInit = true;
   if (!InitBrowserChildMessageManager()) {
     return IPC_FAIL_NO_REASON(this);
   }

   ApplyParentShowInfo(aInfo);
 }
 nsAutoCString spec;
 aLoadState->URI()->GetSpec(spec);

 nsCOMPtr<nsIDocShell> docShell = do_GetInterface(WebNavigation());
 if (!docShell) {
   NS_WARNING("WebNavigation does not have a docshell");
   return IPC_OK();
 }
 docShell->LoadURI(aLoadState, true);

 CrashReporter::RecordAnnotationNSCString(CrashReporter::Annotation::URL,
                                          spec);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvCreateAboutBlankDocumentViewer(
   nsIPrincipal* aPrincipal, nsIPrincipal* aPartitionedPrincipal) {
 if (aPrincipal->GetIsExpandedPrincipal() ||
     aPartitionedPrincipal->GetIsExpandedPrincipal()) {
   return IPC_FAIL(this, "Cannot create document with an expanded principal");
 }
 if (aPrincipal->IsSystemPrincipal() ||
     aPartitionedPrincipal->IsSystemPrincipal()) {
   MOZ_ASSERT_UNREACHABLE(
       "Cannot use CreateAboutBlankDocumentViewer to create system principal "
       "document in content");
   return IPC_OK();
 }

 nsCOMPtr<nsIDocShell> docShell = do_GetInterface(WebNavigation());
 if (!docShell) {
   MOZ_ASSERT_UNREACHABLE("WebNavigation does not have a docshell");
   return IPC_OK();
 }

 nsCOMPtr<nsIURI> currentURI;
 MOZ_ALWAYS_SUCCEEDS(
     WebNavigation()->GetCurrentURI(getter_AddRefs(currentURI)));
 if (!currentURI || !NS_IsAboutBlank(currentURI)) {
   NS_WARNING("Can't create a DocumentViewer unless on about:blank");
   return IPC_OK();
 }

 docShell->CreateAboutBlankDocumentViewer(aPrincipal, aPartitionedPrincipal,
                                          nullptr);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvResumeLoad(
   const uint64_t& aPendingSwitchID, const ParentShowInfo& aInfo) {
 if (!mDidLoadURLInit) {
   mDidLoadURLInit = true;
   if (!InitBrowserChildMessageManager()) {
     return IPC_FAIL_NO_REASON(this);
   }

   ApplyParentShowInfo(aInfo);
 }

 nsresult rv = WebNavigation()->ResumeRedirectedLoad(aPendingSwitchID, -1);
 if (NS_FAILED(rv)) {
   NS_WARNING("WebNavigation()->ResumeRedirectedLoad failed");
 }

 return IPC_OK();
}

nsresult BrowserChild::CloneDocumentTreeIntoSelf(
   const MaybeDiscarded<BrowsingContext>& aSourceBC,
   const embedding::PrintData& aPrintData) {
#ifdef NS_PRINTING
 if (NS_WARN_IF(aSourceBC.IsNullOrDiscarded())) {
   return NS_ERROR_FAILURE;
 }
 nsCOMPtr<Document> sourceDocument = aSourceBC.get()->GetDocument();
 if (NS_WARN_IF(!sourceDocument)) {
   return NS_ERROR_FAILURE;
 }

 nsCOMPtr<nsIDocShell> ourDocShell = do_GetInterface(WebNavigation());
 if (NS_WARN_IF(!ourDocShell)) {
   return NS_ERROR_FAILURE;
 }

 nsCOMPtr<nsIDocumentViewer> viewer;
 ourDocShell->GetDocViewer(getter_AddRefs(viewer));
 if (NS_WARN_IF(!viewer)) {
   return NS_ERROR_FAILURE;
 }

 nsCOMPtr<nsIPrintSettingsService> printSettingsSvc =
     do_GetService("@mozilla.org/gfx/printsettings-service;1");
 if (NS_WARN_IF(!printSettingsSvc)) {
   return NS_ERROR_FAILURE;
 }

 nsCOMPtr<nsIPrintSettings> printSettings;
 nsresult rv =
     printSettingsSvc->CreateNewPrintSettings(getter_AddRefs(printSettings));
 if (NS_WARN_IF(NS_FAILED(rv))) {
   return rv;
 }

 printSettingsSvc->DeserializeToPrintSettings(aPrintData, printSettings);

 RefPtr<Document> clone;
 {
   AutoPrintEventDispatcher dispatcher(*sourceDocument);
   nsAutoScriptBlocker scriptBlocker;
   bool hasInProcessCallbacks = false;
   clone = sourceDocument->CreateStaticClone(
       ourDocShell, viewer, printSettings, &hasInProcessCallbacks);
   if (NS_WARN_IF(!clone)) {
     return NS_ERROR_FAILURE;
   }
 }

 rv = UpdateRemotePrintSettings(aPrintData);
 if (NS_FAILED(rv)) {
   return rv;
 }

#endif
 return NS_OK;
}

mozilla::ipc::IPCResult BrowserChild::RecvCloneDocumentTreeIntoSelf(
   const MaybeDiscarded<BrowsingContext>& aSourceBC,
   const embedding::PrintData& aPrintData,
   CloneDocumentTreeIntoSelfResolver&& aResolve) {
 nsresult rv = NS_OK;

#ifdef NS_PRINTING
 rv = CloneDocumentTreeIntoSelf(aSourceBC, aPrintData);
#endif

 aResolve(NS_SUCCEEDED(rv));
 return IPC_OK();
}

nsresult BrowserChild::UpdateRemotePrintSettings(
   const embedding::PrintData& aPrintData) {
#ifdef NS_PRINTING
 nsCOMPtr<nsIDocShell> ourDocShell = do_GetInterface(WebNavigation());
 if (NS_WARN_IF(!ourDocShell)) {
   return NS_ERROR_FAILURE;
 }

 RefPtr<Document> doc = ourDocShell->GetExtantDocument();
 if (NS_WARN_IF(!doc) || NS_WARN_IF(!doc->IsStaticDocument())) {
   return NS_ERROR_FAILURE;
 }

 RefPtr<BrowsingContext> bc = ourDocShell->GetBrowsingContext();
 if (NS_WARN_IF(!bc)) {
   return NS_ERROR_FAILURE;
 }

 nsCOMPtr<nsIPrintSettingsService> printSettingsSvc =
     do_GetService("@mozilla.org/gfx/printsettings-service;1");
 if (NS_WARN_IF(!printSettingsSvc)) {
   return NS_ERROR_FAILURE;
 }

 nsCOMPtr<nsIPrintSettings> printSettings;
 nsresult rv =
     printSettingsSvc->CreateNewPrintSettings(getter_AddRefs(printSettings));
 if (NS_WARN_IF(NS_FAILED(rv))) {
   return rv;
 }

 printSettingsSvc->DeserializeToPrintSettings(aPrintData, printSettings);

 bc->PreOrderWalk([&](BrowsingContext* aBc) {
   if (nsCOMPtr<nsIDocShell> inProcess = aBc->GetDocShell()) {
     nsCOMPtr<nsIDocumentViewer> viewer;
     inProcess->GetDocViewer(getter_AddRefs(viewer));
     if (NS_WARN_IF(!viewer)) {
       return BrowsingContext::WalkFlag::Skip;
     }
     // The CanRunScript analysis is not smart enough to see across
     // the std::function PreOrderWalk uses, so we cheat a bit here, but it is
     // fine because PreOrderWalk does deal with arbitrary script changing the
     // BC tree, and our code above is simple enough and keeps strong refs to
     // everything.
     ([&]() MOZ_CAN_RUN_SCRIPT_BOUNDARY {
       RefPtr<RemotePrintJobChild> printJob =
           static_cast<RemotePrintJobChild*>(
               aPrintData.remotePrintJob().AsChild());
       viewer->SetPrintSettingsForSubdocument(printSettings, printJob);
     }());
   } else if (RefPtr<BrowserBridgeChild> remoteChild =
                  BrowserBridgeChild::GetFrom(aBc->GetEmbedderElement())) {
     (void)remoteChild->SendUpdateRemotePrintSettings(aPrintData);
     return BrowsingContext::WalkFlag::Skip;
   }
   return BrowsingContext::WalkFlag::Next;
 });
#endif

 return NS_OK;
}

mozilla::ipc::IPCResult BrowserChild::RecvUpdateRemotePrintSettings(
   const embedding::PrintData& aPrintData) {
#ifdef NS_PRINTING
 UpdateRemotePrintSettings(aPrintData);
#endif

 return IPC_OK();
}

void BrowserChild::DoFakeShow(const ParentShowInfo& aParentShowInfo) {
 OwnerShowInfo ownerInfo{LayoutDeviceIntSize(), ScrollbarPreference::Auto,
                         nsSizeMode_Normal};
 RecvShow(aParentShowInfo, ownerInfo);
 mDidFakeShow = true;
}

void BrowserChild::ApplyParentShowInfo(const ParentShowInfo& aInfo) {
 // Even if we already set real show info, the dpi / rounding & scale may still
 // be invalid (if BrowserParent wasn't able to get widget it would just send
 // 0). So better to always set up-to-date values here.
 if (aInfo.dpi() > 0) {
   mPuppetWidget->UpdateBackingScaleCache(aInfo.dpi(), aInfo.widgetRounding(),
                                          aInfo.defaultScale());
 }

 if (mDidSetRealShowInfo) {
   return;
 }

 if (!aInfo.fakeShowInfo()) {
   // Once we've got one ShowInfo from parent, no need to update the values
   // anymore.
   mDidSetRealShowInfo = true;
 }

 mIsTransparent = aInfo.isTransparent();
}

mozilla::ipc::IPCResult BrowserChild::RecvShow(
   const ParentShowInfo& aParentInfo, const OwnerShowInfo& aOwnerInfo) {
 bool res = true;

 mPuppetWidget->SetSizeMode(aOwnerInfo.sizeMode());
 if (!mDidFakeShow) {
   nsCOMPtr<nsIBaseWindow> baseWindow = do_QueryInterface(WebNavigation());
   if (!baseWindow) {
     NS_ERROR("WebNavigation() doesn't QI to nsIBaseWindow");
     return IPC_FAIL_NO_REASON(this);
   }

   baseWindow->SetVisibility(true);
   res = InitBrowserChildMessageManager();
 }

 ApplyParentShowInfo(aParentInfo);

 if (!mIsTopLevel) {
   RecvScrollbarPreferenceChanged(aOwnerInfo.scrollbarPreference());
 }

 if (!res) {
   return IPC_FAIL_NO_REASON(this);
 }

 UpdateVisibility();

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvInitRendering(
   const TextureFactoryIdentifier& aTextureFactoryIdentifier,
   const layers::LayersId& aLayersId,
   const CompositorOptions& aCompositorOptions, const bool& aLayersConnected) {
 mLayersConnected = Some(aLayersConnected);
 mLayersConnectRequested = Some(aLayersConnected);
 InitRenderingState(aTextureFactoryIdentifier, aLayersId, aCompositorOptions);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvScrollbarPreferenceChanged(
   ScrollbarPreference aPreference) {
 MOZ_ASSERT(!mIsTopLevel,
            "Scrollbar visibility should be derived from chrome flags for "
            "top-level windows");
 if (nsCOMPtr<nsIDocShell> docShell = do_GetInterface(WebNavigation())) {
   nsDocShell::Cast(docShell)->SetScrollbarPreference(aPreference);
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvCompositorOptionsChanged(
   const CompositorOptions& aNewOptions) {
 MOZ_ASSERT(mCompositorOptions);

 // The only compositor option we currently support changing is APZ
 // enablement. Even that is only partially supported for now:
 //   * Going from APZ to non-APZ is fine - we just flip the stored flag.
 //     Note that we keep the actors (mApzcTreeManager, and the APZChild
 //     created in InitAPZState()) around (read on for why).
 //   * Going from non-APZ to APZ is only supported if we were using
 //     APZ initially (at InitRendering() time) and we are transitioning
 //     back. In this case, we just reuse the actors which we kept around.
 //     Fully supporting a non-APZ to APZ transition (i.e. even in cases
 //     where we initialized as non-APZ) would require setting up the actors
 //     here. (In that case, we would also have the options of destroying
 //     the actors in the APZ --> non-APZ case, and always re-creating them
 //     during a non-APZ --> APZ transition).
 mCompositorOptions->SetUseAPZ(aNewOptions.UseAPZ());
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvUpdateDimensions(
   const DimensionInfo& aDimensionInfo) {
 if (mLayersConnected.isNothing()) {
   return IPC_OK();
 }

 mUnscaledOuterRect = aDimensionInfo.rect();
 mClientOffset = aDimensionInfo.clientOffset();
 mChromeOffset = aDimensionInfo.chromeOffset();
 MOZ_ASSERT_IF(!IsTopLevel(), mChromeOffset == LayoutDeviceIntPoint());

 SetUnscaledInnerSize(aDimensionInfo.size());
 if (!mHasValidInnerSize && aDimensionInfo.size().width != 0 &&
     aDimensionInfo.size().height != 0) {
   mHasValidInnerSize = true;
 }

 const LayoutDeviceIntSize innerSize = GetInnerSize();
 // Make sure to set the size on the document viewer first.  The
 // MobileViewportManager needs the content viewer size to be updated before
 // the reflow, otherwise it gets a stale size when it computes a new CSS
 // viewport.
 nsCOMPtr<nsIBaseWindow> baseWin = do_QueryInterface(WebNavigation());
 baseWin->SetPositionAndSize(0, 0, innerSize.width, innerSize.height,
                             nsIBaseWindow::eRepaint);

 const LayoutDeviceIntRect widgetRect(
     GetOuterRect().TopLeft() + mClientOffset + mChromeOffset, innerSize);
 mPuppetWidget->Resize(widgetRect / mPuppetWidget->GetDesktopToDeviceScale(),
                       true);

 RecvSafeAreaInsetsChanged(mPuppetWidget->GetSafeAreaInsets());

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvSizeModeChanged(
   const nsSizeMode& aSizeMode) {
 mPuppetWidget->SetSizeMode(aSizeMode);
 if (!mPuppetWidget->IsVisible()) {
   return IPC_OK();
 }
 nsCOMPtr<Document> document(GetTopLevelDocument());
 if (!document) {
   return IPC_OK();
 }
 nsPresContext* presContext = document->GetPresContext();
 if (presContext) {
   presContext->SizeModeChanged(aSizeMode);
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvChildToParentMatrix(
   const Maybe<gfx::Matrix4x4>& aMatrix,
   const ScreenRect& aTopLevelViewportVisibleRectInBrowserCoords) {
 mChildToParentConversionMatrix =
     LayoutDeviceToLayoutDeviceMatrix4x4::FromUnknownMatrix(aMatrix);
 mTopLevelViewportVisibleRectInBrowserCoords =
     aTopLevelViewportVisibleRectInBrowserCoords;

 if (mContentTransformPromise) {
   mContentTransformPromise->MaybeResolveWithUndefined();
   mContentTransformPromise = nullptr;
 }

 // Trigger an intersection observation update since ancestor viewports
 // changed.
 if (RefPtr<Document> toplevelDoc = GetTopLevelDocument()) {
   if (nsPresContext* pc = toplevelDoc->GetPresContext()) {
     pc->RefreshDriver()->EnsureIntersectionObservationsUpdateHappens();
   }
 }

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvUpdateRemoteStyle(
   const StyleImageRendering& aImageRendering) {
 BrowsingContext* context = GetBrowsingContext();
 if (!context) {
   return IPC_OK();
 }

 Document* document = context->GetDocument();
 if (!document) {
   return IPC_OK();
 }

 if (document->IsImageDocument()) {
   document->AsImageDocument()->UpdateRemoteStyle(aImageRendering);
 }

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvDynamicToolbarMaxHeightChanged(
   const ScreenIntCoord& aHeight) {
 mDynamicToolbarMaxHeight = aHeight;

 RefPtr<Document> document = GetTopLevelDocument();
 if (!document) {
   return IPC_OK();
 }

 if (RefPtr<nsPresContext> presContext = document->GetPresContext()) {
   presContext->SetDynamicToolbarMaxHeight(aHeight);
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvDynamicToolbarOffsetChanged(
   const ScreenIntCoord& aOffset) {
 RefPtr<Document> document = GetTopLevelDocument();
 if (!document) {
   return IPC_OK();
 }

 if (nsPresContext* presContext = document->GetPresContext()) {
   presContext->UpdateDynamicToolbarOffset(aOffset);
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvKeyboardHeightChanged(
   const ScreenIntCoord& aHeight) {
#if defined(MOZ_WIDGET_ANDROID)
 mKeyboardHeight = aHeight;

 RefPtr<Document> document = GetTopLevelDocument();
 if (!document) {
   return IPC_OK();
 }

 if (nsPresContext* presContext = document->GetPresContext()) {
   presContext->UpdateKeyboardHeight(aHeight);
 }
#endif
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvAndroidPipModeChanged(bool aPipMode) {
 if (mInAndroidPipMode == aPipMode) {
   return IPC_OK();
 }
 mInAndroidPipMode = aPipMode;
 if (RefPtr<Document> document = GetTopLevelDocument()) {
   if (nsPresContext* presContext = document->GetPresContext()) {
     presContext->MediaFeatureValuesChanged(
         {MediaFeatureChangeReason::DisplayModeChange},
         MediaFeatureChangePropagation::JustThisDocument);
   }
   nsContentUtils::DispatchEventOnlyToChrome(
       document, document,
       aPipMode ? u"MozAndroidPipModeEntered"_ns
                : u"MozAndroidPipModeExited"_ns,
       CanBubble::eYes, Cancelable::eNo, /* DefaultAction */ nullptr);
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvSuppressDisplayport(
   const bool& aEnabled) {
 if (RefPtr<PresShell> presShell = GetTopLevelPresShell()) {
   presShell->SuppressDisplayport(aEnabled);
 }
 return IPC_OK();
}

void BrowserChild::HandleDoubleTap(const CSSPoint& aPoint,
                                  const Modifiers& aModifiers,
                                  const ScrollableLayerGuid& aGuid,
                                  const DoubleTapToZoomMetrics& aMetrics) {
 MOZ_LOG(
     sApzChildLog, LogLevel::Debug,
     ("Handling double tap at %s with %p %p\n", ToString(aPoint).c_str(),
      mBrowserChildMessageManager ? mBrowserChildMessageManager->GetWrapper()
                                  : nullptr,
      mBrowserChildMessageManager.get()));

 if (!mBrowserChildMessageManager) {
   return;
 }

 // Note: there is nothing to do with the modifiers here, as we are not
 // synthesizing any sort of mouse event.
 RefPtr<Document> document = GetTopLevelDocument();
 ZoomTarget zoomTarget = CalculateRectToZoomTo(document, aPoint, aMetrics);
 // The double-tap can be dispatched by any scroll frame (so |aGuid| could be
 // the guid of any scroll frame), but the zoom-to-rect operation must be
 // performed by the root content scroll frame, so query its identifiers
 // for the SendZoomToRect() call rather than using the ones from |aGuid|.
 uint32_t presShellId;
 ViewID viewId;
 if (APZCCallbackHelper::GetOrCreateScrollIdentifiers(
         document->GetDocumentElement(), &presShellId, &viewId) &&
     mApzcTreeManager) {
   ScrollableLayerGuid guid(mLayersId, presShellId, viewId);

   mApzcTreeManager->ZoomToRect(guid, zoomTarget,
                                ZoomToRectBehavior::DEFAULT_BEHAVIOR);
 }
}

mozilla::ipc::IPCResult BrowserChild::RecvHandleTap(
   const GeckoContentController::TapType& aType,
   const LayoutDevicePoint& aPoint, const Modifiers& aModifiers,
   const ScrollableLayerGuid& aGuid, const uint64_t& aInputBlockId,
   const Maybe<DoubleTapToZoomMetrics>& aDoubleTapToZoomMetrics) {
 // IPDL doesn't hold a strong reference to protocols as they're not required
 // to be refcounted. This function can run script, which may trigger a nested
 // event loop, which may release this, so we hold a strong reference here.
 RefPtr<BrowserChild> kungFuDeathGrip(this);
 RefPtr<PresShell> presShell = GetTopLevelPresShell();
 if (!presShell || !presShell->GetPresContext() || !mAPZEventState) {
   return IPC_OK();
 }
 CSSToLayoutDeviceScale scale(
     presShell->GetPresContext()->CSSToDevPixelScale());
 CSSPoint point = aPoint / scale;

 // Stash the guid in InputAPZContext so that when the visual-to-layout
 // transform is applied to the event's coordinates, we use the right transform
 // based on the scroll frame being targeted.
 // The other values don't really matter.
 InputAPZContext context(aGuid, aInputBlockId, nsEventStatus_eSentinel);

 switch (aType) {
   case GeckoContentController::TapType::eSingleTap:
     if (mBrowserChildMessageManager) {
       RefPtr<APZEventState> eventState(mAPZEventState);
       eventState->ProcessSingleTap(point, scale, aModifiers, 1,
                                    aInputBlockId);
     }
     break;
   case GeckoContentController::TapType::eDoubleTap:
     HandleDoubleTap(point, aModifiers, aGuid, *aDoubleTapToZoomMetrics);
     break;
   case GeckoContentController::TapType::eSecondTap:
     if (mBrowserChildMessageManager) {
       RefPtr<APZEventState> eventState(mAPZEventState);
       eventState->ProcessSingleTap(point, scale, aModifiers, 2,
                                    aInputBlockId);
     }
     break;
   case GeckoContentController::TapType::eLongTap:
     if (mBrowserChildMessageManager) {
       RefPtr<APZEventState> eventState(mAPZEventState);
       eventState->ProcessLongTap(presShell, point, scale, aModifiers,
                                  aInputBlockId);
     }
     break;
   case GeckoContentController::TapType::eLongTapUp:
     if (mBrowserChildMessageManager) {
       RefPtr<APZEventState> eventState(mAPZEventState);
       eventState->ProcessLongTapUp(presShell, point, scale, aModifiers);
     }
     break;
 }

 // mAPZEventState may not dispatch the compatibility mouse events.  Therefore,
 // we should release the pointer capturing element at the last ePointerUp
 // here.
 PointerEventHandler::ReleasePointerCapturingElementAtLastPointerUp();

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPriorityHandleTap(
   const GeckoContentController::TapType& aType,
   const LayoutDevicePoint& aPoint, const Modifiers& aModifiers,
   const ScrollableLayerGuid& aGuid, const uint64_t& aInputBlockId,
   const Maybe<DoubleTapToZoomMetrics>& aDoubleTapToZoomMetrics) {
 // IPDL doesn't hold a strong reference to protocols as they're not required
 // to be refcounted. This function can run script, which may trigger a nested
 // event loop, which may release this, so we hold a strong reference here.
 RefPtr<BrowserChild> kungFuDeathGrip(this);
 return RecvHandleTap(aType, aPoint, aModifiers, aGuid, aInputBlockId,
                      aDoubleTapToZoomMetrics);
}

void BrowserChild::NotifyAPZStateChange(
   const ViewID& aViewId,
   const layers::GeckoContentController::APZStateChange& aChange,
   const int& aArg, Maybe<uint64_t> aInputBlockId) {
 if (mAPZEventState) {
   mAPZEventState->ProcessAPZStateChange(aViewId, aChange, aArg,
                                         aInputBlockId);
 }
 nsCOMPtr<nsIObserverService> observerService =
     mozilla::services::GetObserverService();
 if (aChange ==
     layers::GeckoContentController::APZStateChange::eTransformEnd) {
   // This is used by tests to determine when the APZ is done doing whatever
   // it's doing. XXX generify this as needed when writing additional tests.
   observerService->NotifyObservers(nullptr, "APZ:TransformEnd", nullptr);
   observerService->NotifyObservers(nullptr, "PanZoom:StateChange",
                                    u"NOTHING");
 } else if (aChange ==
            layers::GeckoContentController::APZStateChange::eTransformBegin) {
   observerService->NotifyObservers(nullptr, "PanZoom:StateChange",
                                    u"PANNING");
 }
}

void BrowserChild::StartScrollbarDrag(
   const layers::AsyncDragMetrics& aDragMetrics) {
 ScrollableLayerGuid guid(mLayersId, aDragMetrics.mPresShellId,
                          aDragMetrics.mViewId);

 if (mApzcTreeManager) {
   mApzcTreeManager->StartScrollbarDrag(guid, aDragMetrics);
 }
}

void BrowserChild::ZoomToRect(const uint32_t& aPresShellId,
                             const ScrollableLayerGuid::ViewID& aViewId,
                             const CSSRect& aRect, const uint32_t& aFlags) {
 ScrollableLayerGuid guid(mLayersId, aPresShellId, aViewId);

 if (mApzcTreeManager) {
   mApzcTreeManager->ZoomToRect(guid, ZoomTarget{aRect}, aFlags);
 }
}

mozilla::ipc::IPCResult BrowserChild::RecvActivate(uint64_t aActionId) {
 MOZ_ASSERT(mWebBrowser);
 mWebBrowser->FocusActivate(aActionId);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvDeactivate(uint64_t aActionId) {
 MOZ_ASSERT(mWebBrowser);
 mWebBrowser->FocusDeactivate(aActionId);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvStopIMEStateManagement() {
 IMEStateManager::StopIMEStateManagement();
 return IPC_OK();
}

void BrowserChild::ProcessPendingCoalescedTouchData() {
 MOZ_ASSERT(StaticPrefs::dom_events_coalesce_touchmove());

 if (mCoalescedTouchData.IsEmpty()) {
   return;
 }

 if (mCoalescedTouchMoveEventFlusher) {
   mCoalescedTouchMoveEventFlusher->RemoveObserver();
 }

 UniquePtr<WidgetTouchEvent> touchMoveEvent =
     mCoalescedTouchData.TakeCoalescedEvent();
 (void)RecvRealTouchEvent(*touchMoveEvent,
                          mCoalescedTouchData.GetScrollableLayerGuid(),
                          mCoalescedTouchData.GetInputBlockId(),
                          mCoalescedTouchData.GetApzResponse());
}

void BrowserChild::ProcessPendingCoalescedMouseDataAndDispatchEvents() {
 if (!mCoalesceMouseMoveEvents || !mCoalescedMouseEventFlusher) {
   // We don't enable mouse coalescing or we are destroying BrowserChild.
   return;
 }

 // We may reentry the event loop and push more data to
 // mToBeDispatchedMouseData while dispatching an event.

 // We may have some pending coalesced data while dispatch an event and reentry
 // the event loop. In that case we don't have chance to consume the remaining
 // pending data until we get new mouse events. Get some helps from
 // mCoalescedMouseEventFlusher to trigger it.
 mCoalescedMouseEventFlusher->StartObserver();

 while (mToBeDispatchedMouseData.GetSize() > 0) {
   UniquePtr<CoalescedMouseData> data(
       static_cast<CoalescedMouseData*>(mToBeDispatchedMouseData.PopFront()));

   UniquePtr<WidgetMouseEvent> event = data->TakeCoalescedEvent();
   if (event) {
     // When the real mouse event receivers put the received event into the
     // queue, they should dispatch eMouseRawUpdate event immediately (if and
     // only if it's required).  Therefore, unless the event is the last one
     // of the queue, the pending events should've been marked as "Do not
     // convert to "pointerrawupdate".
     MOZ_ASSERT_IF(mToBeDispatchedMouseData.GetSize() > 0,
                   !event->convertToPointerRawUpdate);
     // Dispatch the pending events. Using HandleRealMouseButtonEvent
     // to bypass the coalesce handling in RecvRealMouseMoveEvent. Can't use
     // RecvRealMouseButtonEvent because we may also put some mouse events
     // other than mousemove.
     HandleRealMouseButtonEvent(*event, data->GetScrollableLayerGuid(),
                                data->GetInputBlockId());
   }
 }
 // mCoalescedMouseEventFlusher may be destroyed when reentrying the event
 // loop.
 if (mCoalescedMouseEventFlusher) {
   mCoalescedMouseEventFlusher->RemoveObserver();
 }
}

LayoutDeviceToLayoutDeviceMatrix4x4
BrowserChild::GetChildToParentConversionMatrix() const {
 if (mChildToParentConversionMatrix) {
   return *mChildToParentConversionMatrix;
 }
 LayoutDevicePoint offset(GetChromeOffset());
 return LayoutDeviceToLayoutDeviceMatrix4x4::Translation(offset);
}

Maybe<ScreenRect> BrowserChild::GetTopLevelViewportVisibleRectInBrowserCoords()
   const {
 if (!mChildToParentConversionMatrix) {
   return Nothing();
 }
 return Some(mTopLevelViewportVisibleRectInBrowserCoords);
}

void BrowserChild::FlushAllCoalescedMouseData() {
 MOZ_ASSERT(mCoalesceMouseMoveEvents);

 // Move all entries from mCoalescedMouseData to mToBeDispatchedMouseData.
 for (const auto& data : mCoalescedMouseData.Values()) {
   if (!data || data->IsEmpty()) {
     continue;
   }
   UniquePtr<CoalescedMouseData> dispatchData =
       MakeUnique<CoalescedMouseData>();

   dispatchData->RetrieveDataFrom(*data);
   mToBeDispatchedMouseData.Push(dispatchData.release());
 }
 mCoalescedMouseData.Clear();
}

mozilla::ipc::IPCResult BrowserChild::RecvRealMouseMoveEvent(
   const WidgetMouseEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 if (mCoalesceMouseMoveEvents && mCoalescedMouseEventFlusher) {
   CoalescedMouseData* data =
       mCoalescedMouseData.GetOrInsertNew(aEvent.pointerId);
   MOZ_ASSERT(data);
   if (data->CanCoalesce(aEvent, aGuid, aInputBlockId,
                         mCoalescedMouseEventFlusher->GetRefreshDriver())) {
     // Callback doesn't support if the event is coalesced.
     MOZ_ASSERT_IF(!data->IsEmpty(), aEvent.mCallbackId.isNothing());

     // We don't need to dispatch aEvent immediately.  However, we need to
     // dispatch eMouseRawUpdate immediately if there is a `pointerrawupdate`
     // event listener.  Therefore, the cloned event in the queue shouldn't
     // cause eMouseRawUpdate later when it'll be dispatched.
     WidgetMouseEvent pendingMouseMoveEvent(aEvent);
     // We don't want to dispatch aEvent immediately, so the cloned event
     // should track the cllback id. And the callback id of cloned event will
     // be moved again if there is no coalesced data yet when coalescing.
     pendingMouseMoveEvent.mCallbackId = std::move(aEvent.mCallbackId);
     pendingMouseMoveEvent.convertToPointerRawUpdate = false;
     data->Coalesce(pendingMouseMoveEvent, aGuid, aInputBlockId);
     mCoalescedMouseEventFlusher->StartObserver();
     HandleMouseRawUpdateEvent(pendingMouseMoveEvent, aGuid, aInputBlockId);
     return IPC_OK();
   }

   // Can't coalesce current mousemove event. Put the coalesced mousemove data
   // with the same pointer id to mToBeDispatchedMouseData, coalesce the
   // current one, and process all pending data in mToBeDispatchedMouseData.
   UniquePtr<CoalescedMouseData> dispatchData =
       MakeUnique<CoalescedMouseData>();

   dispatchData->RetrieveDataFrom(*data);
   mToBeDispatchedMouseData.Push(dispatchData.release());

   // Put new data to replace the old one in the hash table.
   CoalescedMouseData* newData =
       mCoalescedMouseData
           .InsertOrUpdate(aEvent.pointerId, MakeUnique<CoalescedMouseData>())
           .get();
   // We don't want to dispatch aEvent immediately.  However, we need to
   // dispatch eMouseRawUpdate immediately if there is a `pointerrawupdate`
   // event listener.  Therefore, the cloned event in the queue shouldn't
   // cause eMouseRawUpdate later when it'll be dispatched.
   WidgetMouseEvent pendingMouseMoveEvent(aEvent);
   // The cloned event should track the cllback id. And the callback id of
   // cloned event will be moved again if there is no coalesced data yet when
   // coalescing.
   pendingMouseMoveEvent.mCallbackId = std::move(aEvent.mCallbackId);
   pendingMouseMoveEvent.convertToPointerRawUpdate = false;
   newData->Coalesce(pendingMouseMoveEvent, aGuid, aInputBlockId);

   // Dispatch all pending mouse events which does NOT include aEvent.
   ProcessPendingCoalescedMouseDataAndDispatchEvents();

   mCoalescedMouseEventFlusher->StartObserver();
   // Finally, dispatch eMouseRawUpdate for aEvent right now.
   HandleMouseRawUpdateEvent(pendingMouseMoveEvent, aGuid, aInputBlockId);
   return IPC_OK();
 }

 if (!RecvRealMouseButtonEvent(aEvent, aGuid, aInputBlockId)) {
   return IPC_FAIL_NO_REASON(this);
 }
 return IPC_OK();
}

void BrowserChild::HandleMouseRawUpdateEvent(
   const WidgetMouseEvent& aPendingMouseEvent,
   const ScrollableLayerGuid& aGuid, const uint64_t& aInputBlockId) {
 // If there is no window containing pointerrawupdate event listeners or the
 // event is a synthesized mousemove, we don't need to dispatch eMouseRawUpdate
 // event.
 if (!mPointerRawUpdateWindowCount || aPendingMouseEvent.IsSynthesized()) {
   return;
 }
 WidgetMouseEvent mouseRawUpdateEvent(aPendingMouseEvent);
 mouseRawUpdateEvent.mMessage = eMouseRawUpdate;
 // PointerEvent.button should always be -1 if the source event is eMouseMove.
 // PointerEventHandler cannot distinguish whether it's caused by
 // eMouseDown/eMouseUp or eMouseMove.  Therefore, we need to set -1
 // (eNotPressed) here.
 mouseRawUpdateEvent.mButton = MouseButton::eNotPressed;
 mouseRawUpdateEvent.mCoalescedWidgetEvents = nullptr;
 mouseRawUpdateEvent.convertToPointer = true;
 // Nobody checks `convertToPointerRawUpdate` of eMouseRawUpdate event.
 // However, the name indicates that it would cause ePointerRawUpdate.
 // For avoiding to make the developers who watch the value with the debugger
 // confused, here sets it to `true`.
 mouseRawUpdateEvent.convertToPointerRawUpdate = true;
 HandleRealMouseButtonEvent(mouseRawUpdateEvent, aGuid, aInputBlockId);
}

mozilla::ipc::IPCResult BrowserChild::RecvRealMouseMoveEventForTests(
   const WidgetMouseEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 return RecvRealMouseMoveEvent(aEvent, aGuid, aInputBlockId);
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPriorityRealMouseMoveEvent(
   const WidgetMouseEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 return RecvRealMouseMoveEvent(aEvent, aGuid, aInputBlockId);
}

mozilla::ipc::IPCResult
BrowserChild::RecvNormalPriorityRealMouseMoveEventForTests(
   const WidgetMouseEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 return RecvRealMouseMoveEvent(aEvent, aGuid, aInputBlockId);
}

mozilla::ipc::IPCResult BrowserChild::RecvSynthMouseMoveEvent(
   const WidgetMouseEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 if (!RecvRealMouseButtonEvent(aEvent, aGuid, aInputBlockId)) {
   return IPC_FAIL_NO_REASON(this);
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPrioritySynthMouseMoveEvent(
   const WidgetMouseEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 return RecvSynthMouseMoveEvent(aEvent, aGuid, aInputBlockId);
}

mozilla::ipc::IPCResult BrowserChild::RecvRealMouseButtonEvent(
   const WidgetMouseEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 if (mCoalesceMouseMoveEvents && mCoalescedMouseEventFlusher &&
     aEvent.mMessage != eMouseMove) {
   // When receiving a mouse event other than mousemove, we have to dispatch
   // all coalesced events before it. However, we can't dispatch all pending
   // coalesced events directly because we may reentry the event loop while
   // dispatching. To make sure we won't dispatch disorder events, we move all
   // coalesced mousemove events and current event to a deque to dispatch them.
   // When reentrying the event loop and dispatching more events, we put new
   // events in the end of the nsQueue and dispatch events from the beginning.
   FlushAllCoalescedMouseData();

   UniquePtr<CoalescedMouseData> dispatchData =
       MakeUnique<CoalescedMouseData>();

   // We'll dispatch aEvent immediately via
   // ProcessPendingCoalescedMouseDataAndDispatchEvents().
   // Therefore, PresShell should convert it to eMouseRawUpdate when it starts
   // handling aEvent if and only if there is a `pointerrawupdate` event
   // listener.  Therefore, let's assert the allowing flag to convert it to
   // eMouseRawUpdate here.
   MOZ_ASSERT(aEvent.convertToPointerRawUpdate);
   dispatchData->Coalesce(aEvent, aGuid, aInputBlockId);

   mToBeDispatchedMouseData.Push(dispatchData.release());
   ProcessPendingCoalescedMouseDataAndDispatchEvents();
   return IPC_OK();
 }
 HandleRealMouseButtonEvent(aEvent, aGuid, aInputBlockId);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvRealPointerButtonEvent(
   const WidgetPointerEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 return RecvRealMouseButtonEvent(aEvent, aGuid, aInputBlockId);
}

void BrowserChild::HandleRealMouseButtonEvent(const WidgetMouseEvent& aEvent,
                                             const ScrollableLayerGuid& aGuid,
                                             const uint64_t& aInputBlockId) {
 AutoSynthesizedEventResponder<WidgetMouseEvent> responder(this, aEvent);

 Maybe<WidgetPointerEvent> pointerEvent;
 Maybe<WidgetMouseEvent> mouseEvent;
 if (aEvent.mClass == ePointerEventClass) {
   pointerEvent.emplace(aEvent);
 } else {
   mouseEvent.emplace(aEvent);
 }
 WidgetMouseEvent& localEvent =
     pointerEvent.isSome() ? pointerEvent.ref() : mouseEvent.ref();
 localEvent.mWidget = mPuppetWidget;

 // We need one InputAPZContext here to propagate |aGuid| to places in
 // SendSetTargetAPZCNotification() which apply the visual-to-layout transform,
 // and another below to propagate the |postLayerization| flag (whose value
 // we don't know until SendSetTargetAPZCNotification() returns) into
 // the event dispatch code.
 InputAPZContext context1(aGuid, aInputBlockId, nsEventStatus_eSentinel);

 // Mouse events like eMouseEnterIntoWidget, that are created in the parent
 // process EventStateManager code, have an input block id which they get from
 // the InputAPZContext in the parent process stack. However, they did not
 // actually go through the APZ code and so their mHandledByAPZ flag is false.
 // Since thos events didn't go through APZ, we don't need to send
 // notifications for them.
 RefPtr<DisplayportSetListener> postLayerization;
 if (aInputBlockId && localEvent.mFlags.mHandledByAPZ) {
   nsCOMPtr<Document> document(GetTopLevelDocument());
   postLayerization = APZCCallbackHelper::SendSetTargetAPZCNotification(
       mPuppetWidget, document, localEvent, aGuid.mLayersId, aInputBlockId);
 }

 InputAPZContext context2(aGuid, aInputBlockId, nsEventStatus_eSentinel,
                          postLayerization != nullptr);

 DispatchWidgetEventViaAPZ(localEvent);

 if (aInputBlockId && localEvent.mFlags.mHandledByAPZ && mAPZEventState) {
   mAPZEventState->ProcessMouseEvent(localEvent, aInputBlockId);
 }

 // Do this after the DispatchWidgetEventViaAPZ call above, so that if the
 // mouse event triggered a post-refresh AsyncDragMetrics message to be sent
 // to APZ (from scrollbar dragging in nsSliderFrame), then that will reach
 // APZ before the SetTargetAPZC message. This ensures the drag input block
 // gets the drag metrics before handling the input events.
 if (postLayerization) {
   postLayerization->Register();
 }
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPriorityRealMouseButtonEvent(
   const WidgetMouseEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 return RecvRealMouseButtonEvent(aEvent, aGuid, aInputBlockId);
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPriorityRealPointerButtonEvent(
   const WidgetPointerEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 return RecvNormalPriorityRealMouseButtonEvent(aEvent, aGuid, aInputBlockId);
}

mozilla::ipc::IPCResult BrowserChild::RecvRealMouseEnterExitWidgetEvent(
   const WidgetMouseEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 return RecvRealMouseButtonEvent(aEvent, aGuid, aInputBlockId);
}

mozilla::ipc::IPCResult
BrowserChild::RecvNormalPriorityRealMouseEnterExitWidgetEvent(
   const WidgetMouseEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 return RecvRealMouseButtonEvent(aEvent, aGuid, aInputBlockId);
}

nsEventStatus BrowserChild::DispatchWidgetEventViaAPZ(WidgetGUIEvent& aEvent) {
 aEvent.ResetWaitingReplyFromRemoteProcessState();
 return APZCCallbackHelper::DispatchWidgetEvent(aEvent);
}

void BrowserChild::DispatchCoalescedWheelEvent() {
 UniquePtr<WidgetWheelEvent> wheelEvent =
     mCoalescedWheelData.TakeCoalescedEvent();
 MOZ_ASSERT(wheelEvent);
 DispatchWheelEvent(*wheelEvent, mCoalescedWheelData.GetScrollableLayerGuid(),
                    mCoalescedWheelData.GetInputBlockId());
}

void BrowserChild::DispatchWheelEvent(const WidgetWheelEvent& aEvent,
                                     const ScrollableLayerGuid& aGuid,
                                     const uint64_t& aInputBlockId) {
 WidgetWheelEvent localEvent(aEvent);
 if (aInputBlockId && aEvent.mFlags.mHandledByAPZ) {
   nsCOMPtr<Document> document(GetTopLevelDocument());
   RefPtr<DisplayportSetListener> postLayerization =
       APZCCallbackHelper::SendSetTargetAPZCNotification(
           mPuppetWidget, document, aEvent, aGuid.mLayersId, aInputBlockId);
   if (postLayerization) {
     postLayerization->Register();
   }
 }

 localEvent.mWidget = mPuppetWidget;

 // Stash the guid in InputAPZContext so that when the visual-to-layout
 // transform is applied to the event's coordinates, we use the right transform
 // based on the scroll frame being targeted.
 // The other values don't really matter.
 InputAPZContext context(aGuid, aInputBlockId, nsEventStatus_eSentinel);

 DispatchWidgetEventViaAPZ(localEvent);

 if (localEvent.mCanTriggerSwipe) {
   SendRespondStartSwipeEvent(aInputBlockId, localEvent.TriggersSwipe());
 }

 if (aInputBlockId && aEvent.mFlags.mHandledByAPZ && mAPZEventState) {
   mAPZEventState->ProcessWheelEvent(localEvent, aInputBlockId);
 }
}

mozilla::ipc::IPCResult BrowserChild::RecvMouseWheelEvent(
   const WidgetWheelEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 AutoSynthesizedEventResponder<WidgetWheelEvent> responder(this, aEvent);

 bool isNextWheelEvent = false;
 // We only coalesce the current event when
 // 1. It's eWheel (we don't coalesce eOperationStart and eWheelOperationEnd)
 // 2. It has same attributes as the coalesced wheel event which is not yet
 //    fired.
 if (aEvent.mMessage == eWheel) {
   GetIPCChannel()->PeekMessages(
       [&isNextWheelEvent](const IPC::Message& aMsg) -> bool {
         if (aMsg.type() == mozilla::dom::PBrowser::Msg_MouseWheelEvent__ID) {
           isNextWheelEvent = true;
         }
         return false;  // Stop peeking.
       });

   if (!mCoalescedWheelData.IsEmpty() &&
       !mCoalescedWheelData.CanCoalesce(aEvent, aGuid, aInputBlockId)) {
     DispatchCoalescedWheelEvent();
     MOZ_ASSERT(mCoalescedWheelData.IsEmpty());
   }
   mCoalescedWheelData.Coalesce(aEvent, aGuid, aInputBlockId);

   MOZ_ASSERT(!mCoalescedWheelData.IsEmpty());
   // If the next event isn't a wheel event, make sure we dispatch.
   if (!isNextWheelEvent) {
     DispatchCoalescedWheelEvent();
   }
 } else {
   DispatchWheelEvent(aEvent, aGuid, aInputBlockId);
 }

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPriorityMouseWheelEvent(
   const WidgetWheelEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId) {
 return RecvMouseWheelEvent(aEvent, aGuid, aInputBlockId);
}

mozilla::ipc::IPCResult BrowserChild::RecvRealTouchEvent(
   const WidgetTouchEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId, const nsEventStatus& aApzResponse) {
 MOZ_LOG(sApzChildLog, LogLevel::Debug,
         ("Receiving touch event of type %d\n", aEvent.mMessage));

 if (StaticPrefs::dom_events_coalesce_touchmove()) {
   if (aEvent.mMessage == eTouchEnd || aEvent.mMessage == eTouchStart) {
     ProcessPendingCoalescedTouchData();
   }

   if (aEvent.mMessage != eTouchMove && aEvent.mMessage != eTouchRawUpdate) {
     sConsecutiveTouchMoveCount = 0;
   }
 }

 WidgetTouchEvent localEvent(aEvent);
 localEvent.mWidget = mPuppetWidget;

 // Stash the guid in InputAPZContext so that when the visual-to-layout
 // transform is applied to the event's coordinates, we use the right transform
 // based on the scroll frame being targeted.
 // The other values don't really matter.
 InputAPZContext context(aGuid, aInputBlockId, aApzResponse);

 nsTArray<TouchBehaviorFlags> allowedTouchBehaviors;
 if (localEvent.mMessage == eTouchStart && AsyncPanZoomEnabled()) {
   nsCOMPtr<Document> document = GetTopLevelDocument();
   allowedTouchBehaviors = TouchActionHelper::GetAllowedTouchBehavior(
       mPuppetWidget, document, localEvent);
   if (!allowedTouchBehaviors.IsEmpty() && mApzcTreeManager) {
     mApzcTreeManager->SetAllowedTouchBehavior(aInputBlockId,
                                               allowedTouchBehaviors);
   }
   RefPtr<DisplayportSetListener> postLayerization =
       APZCCallbackHelper::SendSetTargetAPZCNotification(
           mPuppetWidget, document, localEvent, aGuid.mLayersId,
           aInputBlockId);
   if (postLayerization) {
     postLayerization->Register();
   }
 }

 // Dispatch event to content (potentially a long-running operation)
 nsEventStatus status = DispatchWidgetEventViaAPZ(localEvent);

 if (!AsyncPanZoomEnabled()) {
   // We shouldn't have any e10s platforms that have touch events enabled
   // without APZ.
   MOZ_ASSERT(false);
   return IPC_OK();
 }

 if (mAPZEventState) {
   mAPZEventState->ProcessTouchEvent(localEvent, aGuid, aInputBlockId,
                                     aApzResponse, status,
                                     std::move(allowedTouchBehaviors));
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPriorityRealTouchEvent(
   const WidgetTouchEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId, const nsEventStatus& aApzResponse) {
 return RecvRealTouchEvent(aEvent, aGuid, aInputBlockId, aApzResponse);
}

mozilla::ipc::IPCResult BrowserChild::RecvRealTouchMoveEvent(
   const WidgetTouchEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId, const nsEventStatus& aApzResponse) {
 if (StaticPrefs::dom_events_coalesce_touchmove()) {
   ++sConsecutiveTouchMoveCount;
   if (mCoalescedTouchMoveEventFlusher) {
     MOZ_ASSERT(aEvent.mMessage == eTouchMove);
     // NOTE: While dispatching eTouchMove or eTouchRawUpdate,
     // sConsecutiveTouchMoveCount may be changed by the event loop spun,
     // e.g., an event listener uses sync XHR or calling window.alert().
     const auto PostponeDispatchingTouchMove = [&]() {
       return sConsecutiveTouchMoveCount > 1;
     };
     if (mCoalescedTouchData.IsEmpty() ||
         mCoalescedTouchData.CanCoalesce(aEvent, aGuid, aInputBlockId,
                                         aApzResponse)) {
       if (PostponeDispatchingTouchMove()) {
         WidgetTouchEvent pendingTouchMoveEvent(
             aEvent, WidgetTouchEvent::CloneTouches::Yes);
         // We don't dispatch aEvent immediately here.  However, we need to
         // dispatch eTouchRawUpdate immediately if and only if there is a
         // `pointerrawupdate` event listener.  Therefore, the cloned event in
         // the queue and it shouldn't cause eTouchRawUpdate again.
         pendingTouchMoveEvent.SetConvertToPointerRawUpdate(false);
         mCoalescedTouchData.Coalesce(pendingTouchMoveEvent, aGuid,
                                      aInputBlockId, aApzResponse);
         MOZ_ASSERT(PostponeDispatchingTouchMove());
         mCoalescedTouchMoveEventFlusher->StartObserver();
         // Let's notify the web app of `pointerrawupdate` immediately if and
         // only if they listen to it.
         HandleTouchRawUpdateEvent(pendingTouchMoveEvent, aGuid, aInputBlockId,
                                   aApzResponse);
         return IPC_OK();
       }

       // We'll dispatch aEvent via ProcessPendingCoalescedTouchData() below.
       // Therefore, the touches should cause eTouchRawUpdate event.
       MOZ_ASSERT(aEvent.CanConvertToPointerRawUpdate());
       mCoalescedTouchData.Coalesce(aEvent, aGuid, aInputBlockId,
                                    aApzResponse);
       MOZ_ASSERT(!PostponeDispatchingTouchMove());
     } else {
       UniquePtr<WidgetTouchEvent> touchMoveEvent =
           mCoalescedTouchData.TakeCoalescedEvent();
       MOZ_ASSERT(touchMoveEvent->mMessage == eTouchMove);

       // Before dispatching touchMoveEvent, we need to put aEvent into the
       // queue for keeping the event order even if an event listener spins the
       // event loop and we'll receive another touch event.  So, aEvent may be
       // dispatched while we're dispatching touchMoveEvent. Therefore, we need
       // to make it convertible to eTouchRawUpdate.
       MOZ_ASSERT(aEvent.CanConvertToPointerRawUpdate());
       mCoalescedTouchData.Coalesce(aEvent, aGuid, aInputBlockId,
                                    aApzResponse);
       MOZ_ASSERT(!PostponeDispatchingTouchMove());

       // touchMoveEvent was stored by mCoalescedTouchData before receiving
       // aEvent.  Therefore, the receiver should've already dispatched
       // eTouchRawUpdate for dispatching `pointerrawupdate` and let web apps
       // know the update immediately (with sacrificing the performance).
       // Therefore, we don't need to dispatch eTouchRawUpdate here before
       // dispatching the touchMoveEvent.
       MOZ_ASSERT(!touchMoveEvent->CanConvertToPointerRawUpdate());
       const uint32_t generation = mCoalescedTouchData.Generation();
       if (!RecvRealTouchEvent(*touchMoveEvent,
                               mCoalescedTouchData.GetScrollableLayerGuid(),
                               mCoalescedTouchData.GetInputBlockId(),
                               mCoalescedTouchData.GetApzResponse())) {
         return IPC_FAIL_NO_REASON(this);
       }
       // RecvRealTouchEvent() may have caused spinning the event loop and
       // changed sConsecutiveTouchMoveCount.  So, we need to check it now.
       if (PostponeDispatchingTouchMove()) {
         mCoalescedTouchMoveEventFlusher->StartObserver();
         if (generation == mCoalescedTouchData.Generation()) {
           // Let's notify the web app of `pointerrawupdate` immediately if and
           // only if they listen to it.  Additionally, we don't want to notify
           // eTouchRawUpdate when ProcessPendingCoalescedTouchData() is called
           // later.
           mCoalescedTouchData.NotifyTouchRawUpdateOfHandled(aEvent);
           HandleTouchRawUpdateEvent(aEvent, aGuid, aInputBlockId,
                                     aApzResponse);
         }
         return IPC_OK();
       }
     }
     // Flush the pending coalesced touch in order to avoid the first
     // touchmove be overridden by the second one, this contains aEvent.
     ProcessPendingCoalescedTouchData();
     return IPC_OK();
   }
 }

 if (!RecvRealTouchEvent(aEvent, aGuid, aInputBlockId, aApzResponse)) {
   return IPC_FAIL_NO_REASON(this);
 }
 return IPC_OK();
}

void BrowserChild::HandleTouchRawUpdateEvent(
   const WidgetTouchEvent& aPendingTouchEvent,
   const ScrollableLayerGuid& aGuid, const uint64_t& aInputBlockId,
   const nsEventStatus& aApzResponse) {
 if (!mPointerRawUpdateWindowCount) {
   return;  // There is no window containing pointerrawupdate event listeners
 }

 WidgetTouchEvent touchRawUpdateEvent(aPendingTouchEvent,
                                      WidgetTouchEvent::CloneTouches::Yes);
 touchRawUpdateEvent.mMessage = eTouchRawUpdate;
 for (Touch* const touch : touchRawUpdateEvent.mTouches) {
   touch->mMessage = eTouchRawUpdate;
   touch->mCoalescedWidgetEvents = nullptr;
   touch->convertToPointer = true;
   // Although nobody checks `convertToPointerRawUpdate` of eTouchRawUpdate.
   // However, the name indicates it would cause ePointerRawUpdate or not, so,
   // for avoiding to make developers confused when they watch the value with
   // the debugger, we should set this to `true`.
   touch->convertToPointerRawUpdate = true;
 }
 RecvRealTouchEvent(touchRawUpdateEvent, aGuid, aInputBlockId, aApzResponse);
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPriorityRealTouchMoveEvent(
   const WidgetTouchEvent& aEvent, const ScrollableLayerGuid& aGuid,
   const uint64_t& aInputBlockId, const nsEventStatus& aApzResponse) {
 return RecvRealTouchMoveEvent(aEvent, aGuid, aInputBlockId, aApzResponse);
}

mozilla::ipc::IPCResult BrowserChild::RecvRealDragEvent(
   const WidgetDragEvent& aEvent, const uint32_t& aDragAction,
   const uint32_t& aDropEffect, nsIPrincipal* aPrincipal,
   nsIPolicyContainer* aPolicyContainer) {
 WidgetDragEvent localEvent(aEvent);
 localEvent.mWidget = mPuppetWidget;

 nsCOMPtr<nsIDragSession> dragSession = GetDragSession();
 DRAGSERVICE_LOGD(
     "[%p] %s | aEvent.mMessage: %s | aDragAction: %u | aDropEffect: %u | "
     "widgetRelativePt: (%d,%d) | dragSession: %p",
     this, __FUNCTION__,
     NS_ConvertUTF16toUTF8(dom::Event::GetEventName(aEvent.mMessage)).get(),
     aDragAction, aDropEffect, static_cast<int>(localEvent.mRefPoint.x),
     static_cast<int>(localEvent.mRefPoint.y), dragSession.get());
 if (dragSession) {
   dragSession->SetDragAction(aDragAction);
   dragSession->SetTriggeringPrincipal(aPrincipal);
   dragSession->SetPolicyContainer(aPolicyContainer);
   RefPtr<DataTransfer> initialDataTransfer = dragSession->GetDataTransfer();
   if (initialDataTransfer) {
     initialDataTransfer->SetDropEffectInt(aDropEffect);
   }
 }

 if (aEvent.mMessage == eDrop) {
   bool canDrop = true;
   if (!dragSession || NS_FAILED(dragSession->GetCanDrop(&canDrop)) ||
       !canDrop) {
     DRAGSERVICE_LOGD("[%p] %s | changed drop to dragexit", this,
                      __FUNCTION__);
     localEvent.mMessage = eDragExit;
   }
 } else if (aEvent.mMessage == eDragOver) {
   if (dragSession) {
     // This will dispatch 'drag' event at the source if the
     // drag transaction started in this process.
     dragSession->FireDragEventAtSource(eDrag, aEvent.mModifiers);
   }
 }

 DispatchWidgetEventViaAPZ(localEvent);
 return IPC_OK();
}

already_AddRefed<DataTransfer> BrowserChild::ConvertToDataTransfer(
   nsIPrincipal* aPrincipal, nsTArray<IPCTransferableData>&& aTransferables,
   EventMessage aMessage) {
 // The extension process should grant access to a protected DataTransfer if
 // the principal permits it (and dom.events.datatransfer.protected.enabled is
 // false).  Otherwise, protected DataTransfer access should only be given to
 // the system.
 if (!aPrincipal || Manager()->GetRemoteType() != EXTENSION_REMOTE_TYPE) {
   aPrincipal = nsContentUtils::GetSystemPrincipal();
 }

 // Check if we are receiving any file objects. If we are we will want
 // to hide any of the other objects coming in from content.
 bool hasFiles = false;
 for (uint32_t i = 0; i < aTransferables.Length() && !hasFiles; ++i) {
   auto& items = aTransferables[i].items();
   for (uint32_t j = 0; j < items.Length() && !hasFiles; ++j) {
     if (items[j].data().type() ==
         IPCTransferableDataType::TIPCTransferableDataBlob) {
       hasFiles = true;
     }
   }
 }
 // Add the entries from the IPC to the new DataTransfer
 RefPtr<DataTransfer> dataTransfer =
     new DataTransfer(nullptr, aMessage, false, Nothing());
 for (uint32_t i = 0; i < aTransferables.Length(); ++i) {
   auto& items = aTransferables[i].items();
   for (uint32_t j = 0; j < items.Length(); ++j) {
     const IPCTransferableDataItem& item = items[j];
     RefPtr<nsVariantCC> variant = new nsVariantCC();
     nsresult rv =
         nsContentUtils::IPCTransferableDataItemToVariant(item, variant);
     if (NS_FAILED(rv)) {
       continue;
     }

     // We should hide this data from content if we have a file, and we
     // aren't a file.
     bool hidden =
         hasFiles && item.data().type() !=
                         IPCTransferableDataType::TIPCTransferableDataBlob;
     dataTransfer->SetDataWithPrincipalFromOtherProcess(
         NS_ConvertUTF8toUTF16(item.flavor()), variant, i, aPrincipal, hidden);
   }
 }
 return dataTransfer.forget();
}

mozilla::ipc::IPCResult BrowserChild::RecvInvokeChildDragSession(
   const MaybeDiscarded<WindowContext>& aSourceWindowContext,
   const MaybeDiscarded<WindowContext>& aSourceTopWindowContext,
   nsIPrincipal* aPrincipal, nsTArray<IPCTransferableData>&& aTransferables,
   const uint32_t& aAction) {
 if (nsCOMPtr<nsIDragService> dragService =
         do_GetService("@mozilla.org/widget/dragservice;1")) {
   nsIWidget* widget = WebWidget();
   dragService->StartDragSession(widget);
   if (RefPtr<nsIDragSession> session = GetDragSession()) {
     session->SetSourceWindowContext(aSourceWindowContext.GetMaybeDiscarded());
     session->SetSourceTopWindowContext(
         aSourceTopWindowContext.GetMaybeDiscarded());
     session->SetDragAction(aAction);
     RefPtr<DataTransfer> dataTransfer = ConvertToDataTransfer(
         aPrincipal, std::move(aTransferables), eDragStart);
     session->SetDataTransfer(dataTransfer);
     DRAGSERVICE_LOGD("[%p] %s | Successfully started dragSession: %p", this,
                      __FUNCTION__, session.get());
   } else {
     DRAGSERVICE_LOGE("[%p] %s | Failed to start dragSession", this,
                      __FUNCTION__);
   }
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvUpdateDragSession(
   nsIPrincipal* aPrincipal, nsTArray<IPCTransferableData>&& aTransferables,
   EventMessage aEventMessage) {
 if (RefPtr<nsIDragSession> session = GetDragSession()) {
   nsCOMPtr<DataTransfer> dataTransfer = ConvertToDataTransfer(
       aPrincipal, std::move(aTransferables), aEventMessage);
   session->SetDataTransfer(dataTransfer);
   DRAGSERVICE_LOGD(
       "[%p] %s | session: %p | aEventMessage: %s | Updated dragSession "
       "dataTransfer",
       this, __FUNCTION__, session.get(),
       NS_ConvertUTF16toUTF8(dom::Event::GetEventName(aEventMessage)).get());
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvEndDragSession(
   const bool& aDoneDrag, const bool& aUserCancelled,
   const LayoutDeviceIntPoint& aDragEndPoint, const uint32_t& aKeyModifiers,
   const uint32_t& aDropEffect) {
 RefPtr<nsIDragSession> dragSession = GetDragSession();
 if (dragSession) {
   DRAGSERVICE_LOGD(
       "[%p] %s | dragSession: %p | aDoneDrag: %s | aUserCancelled: %s | "
       "aDragEndPoint: (%d, %d) | aKeyModifiers: %u | aDropEffect: %u",
       this, __FUNCTION__, dragSession.get(), TrueOrFalse(aDoneDrag),
       TrueOrFalse(aUserCancelled), static_cast<int>(aDragEndPoint.x),
       static_cast<int>(aDragEndPoint.y), aKeyModifiers, aDropEffect);

   if (aUserCancelled) {
     dragSession->UserCancelled();
   }

   RefPtr<DataTransfer> dataTransfer = dragSession->GetDataTransfer();
   if (dataTransfer) {
     dataTransfer->SetDropEffectInt(aDropEffect);
   }
   dragSession->SetDragEndPoint(aDragEndPoint.x, aDragEndPoint.y);
   dragSession->EndDragSession(aDoneDrag, aKeyModifiers);
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvStoreDropTargetAndDelayEndDragSession(
   const LayoutDeviceIntPoint& aPt, uint32_t aDropEffect, uint32_t aDragAction,
   nsIPrincipal* aPrincipal, nsIPolicyContainer* aPolicyContainer) {
 // cf. RecvRealDragEvent
 nsCOMPtr<nsIDragSession> dragSession = GetDragSession();
 MOZ_ASSERT(dragSession);
 DRAGSERVICE_LOGD(
     "[%p] %s | dragSession: %p aPt: (%d, %d) | aDropEffect: %u | "
     "aDragAction: %u",
     this, __FUNCTION__, dragSession.get(), static_cast<int>(aPt.x),
     static_cast<int>(aPt.y), aDropEffect, aDragAction);
 dragSession->SetDragAction(aDragAction);
 dragSession->SetTriggeringPrincipal(aPrincipal);
 dragSession->SetPolicyContainer(aPolicyContainer);
 RefPtr<DataTransfer> initialDataTransfer = dragSession->GetDataTransfer();
 if (initialDataTransfer) {
   initialDataTransfer->SetDropEffectInt(aDropEffect);
 }

 bool canDrop = true;
 if (!dragSession || NS_FAILED(dragSession->GetCanDrop(&canDrop)) ||
     !canDrop) {
   // Don't record the target or delay EDS calls.
   return IPC_OK();
 }

 auto parentToChildTf = GetChildToParentConversionMatrix().MaybeInverse();
 NS_ENSURE_TRUE(parentToChildTf, IPC_OK());
 LayoutDevicePoint floatPt(aPt);
 LayoutDevicePoint floatTf = parentToChildTf->TransformPoint(floatPt);
 WidgetQueryContentEvent queryEvent(true, eQueryDropTargetHittest,
                                    mPuppetWidget);
 queryEvent.mRefPoint = RoundedToInt(floatTf);
 DispatchWidgetEventViaAPZ(queryEvent);
 if (queryEvent.mReply && queryEvent.mReply->mDropElement) {
   mDelayedDropPoint = queryEvent.mRefPoint;
   dragSession->StoreDropTargetAndDelayEndDragSession(
       queryEvent.mReply->mDropElement, queryEvent.mReply->mDropFrame);
 } else {
   MOZ_ASSERT(false, "Didn't get reply from eQueryDropTargetHittest event!");
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult
BrowserChild::RecvDispatchToDropTargetAndResumeEndDragSession(
   bool aShouldDrop, nsTHashSet<nsString>&& aAllowedFilesPaths) {
 DRAGSERVICE_LOGD("[%p] %s | aShouldDrop: %s", this, __FUNCTION__,
                  TrueOrFalse(aShouldDrop));
 nsCOMPtr<nsIDragSession> dragSession = GetDragSession();
 MOZ_ASSERT(dragSession);
 RefPtr<nsIWidget> widget = mPuppetWidget;
 nsTHashSet<nsString> allowedPaths =
     aShouldDrop ? std::move(aAllowedFilesPaths) : nsTHashSet<nsString>();
 dragSession->DispatchToDropTargetAndResumeEndDragSession(
     widget, mDelayedDropPoint, aShouldDrop, allowedPaths);
 mDelayedDropPoint = {};
 return IPC_OK();
}

void BrowserChild::RequestEditCommands(NativeKeyBindingsType aType,
                                      const WidgetKeyboardEvent& aEvent,
                                      nsTArray<CommandInt>& aCommands) {
 MOZ_ASSERT(aCommands.IsEmpty());

 if (NS_WARN_IF(aEvent.IsEditCommandsInitialized(aType))) {
   aCommands = aEvent.EditCommandsConstRef(aType).Clone();
   return;
 }

 switch (aType) {
   case NativeKeyBindingsType::SingleLineEditor:
   case NativeKeyBindingsType::MultiLineEditor:
   case NativeKeyBindingsType::RichTextEditor:
     break;
   default:
     MOZ_ASSERT_UNREACHABLE("Invalid native key bindings type");
 }

 // Don't send aEvent to the parent process directly because it'll be marked
 // as posted to remote process.
 WidgetKeyboardEvent localEvent(aEvent);
 SendRequestNativeKeyBindings(static_cast<uint32_t>(aType), localEvent,
                              &aCommands);
}

mozilla::ipc::IPCResult BrowserChild::RecvSynthesizedEventResponse(
   const uint64_t& aCallbackId) {
 NS_ENSURE_TRUE(xpc::IsInAutomation(), IPC_FAIL(this, "Unexpected event"));
 mozilla::widget::AutoSynthesizedEventCallbackNotifier::NotifySavedCallback(
     aCallbackId);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvUpdateSHistory() {
 if (mSessionStoreChild) {
   mSessionStoreChild->UpdateSHistoryChanges();
 }
 return IPC_OK();
}

// In case handling repeated keys takes much time, we skip firing new ones.
bool BrowserChild::SkipRepeatedKeyEvent(const WidgetKeyboardEvent& aEvent) {
 if (mRepeatedKeyEventTime.IsNull() || !aEvent.CanSkipInRemoteProcess() ||
     (aEvent.mMessage != eKeyDown && aEvent.mMessage != eKeyPress)) {
   mRepeatedKeyEventTime = TimeStamp();
   mSkipKeyPress = false;
   return false;
 }

 if ((aEvent.mMessage == eKeyDown &&
      (mRepeatedKeyEventTime > aEvent.mTimeStamp)) ||
     (mSkipKeyPress && (aEvent.mMessage == eKeyPress))) {
   // If we skip a keydown event, also the following keypress events should be
   // skipped.
   mSkipKeyPress |= aEvent.mMessage == eKeyDown;
   return true;
 }

 if (aEvent.mMessage == eKeyDown) {
   // If keydown wasn't skipped, nor should the possible following keypress.
   mRepeatedKeyEventTime = TimeStamp();
   mSkipKeyPress = false;
 }
 return false;
}

void BrowserChild::UpdateRepeatedKeyEventEndTime(
   const WidgetKeyboardEvent& aEvent) {
 if (aEvent.mIsRepeat &&
     (aEvent.mMessage == eKeyDown || aEvent.mMessage == eKeyPress)) {
   mRepeatedKeyEventTime = TimeStamp::Now();
 }
}

mozilla::ipc::IPCResult BrowserChild::RecvRealKeyEvent(
   const WidgetKeyboardEvent& aEvent, const nsID& aUUID) {
 MOZ_ASSERT_IF(aEvent.mMessage == eKeyPress,
               aEvent.AreAllEditCommandsInitialized());

 // If content code called preventDefault() on a keydown event, then we don't
 // want to process any following keypress events which is caused by the
 // preceding keydown (i.e., default action of the preceding keydown).
 // In other words, if the keypress is not a default action of the preceding
 // keydown, we should not stop dispatching keypress event even if the
 // immediate preceding keydown was consumed.
 const bool isPrecedingKeyDownEventConsumed =
     aEvent.mMessage == eKeyPress && mPreviousConsumedKeyDownCode.isSome() &&
     mPreviousConsumedKeyDownCode.value() == aEvent.mCodeNameIndex;

 WidgetKeyboardEvent localEvent(aEvent);
 localEvent.mWidget = mPuppetWidget;
 localEvent.mUniqueId = aEvent.mUniqueId;

 if (!SkipRepeatedKeyEvent(aEvent) && !isPrecedingKeyDownEventConsumed) {
   nsEventStatus status = DispatchWidgetEventViaAPZ(localEvent);

   // Update the end time of the possible repeated event so that we can skip
   // some incoming events in case event handling took long time.
   UpdateRepeatedKeyEventEndTime(localEvent);

   if (aEvent.mMessage == eKeyDown) {
     // If eKeyDown is consumed, we should stop dispatching the following
     // eKeyPress events since the events are default action of eKeyDown.
     // FIXME:  We should synthesize eKeyPress in this process (bug 1181501).
     if (status == nsEventStatus_eConsumeNoDefault) {
       MOZ_ASSERT_IF(!aEvent.mFlags.mIsSynthesizedForTests,
                     aEvent.mCodeNameIndex != CODE_NAME_INDEX_USE_STRING);
       // If mPreviousConsumedKeyDownCode is not Nothing, 2 or more keys may be
       // pressed at same time and their eKeyDown are consumed.  However, we
       // forget the previous eKeyDown event result here and that might cause
       // dispatching eKeyPress events caused by the previous eKeyDown in
       // theory.  However, this should not occur because eKeyPress should be
       // fired before another eKeyDown, although it's depend on how the native
       // keyboard event handler is implemented.
       mPreviousConsumedKeyDownCode = Some(aEvent.mCodeNameIndex);
     }
     // If eKeyDown is not consumed but we know preceding eKeyDown is consumed,
     // we need to forget it since we should not stop dispatching following
     // eKeyPress events which are default action of current eKeyDown.
     else if (mPreviousConsumedKeyDownCode.isSome() &&
              aEvent.mCodeNameIndex == mPreviousConsumedKeyDownCode.value()) {
       mPreviousConsumedKeyDownCode.reset();
     }
   }
   // eKeyPress is a default action of eKeyDown.  Therefore, eKeyPress is fired
   // between eKeyDown and eKeyUp.  So, received an eKeyUp for eKeyDown which
   // was consumed means that following eKeyPress events should be dispatched.
   // Therefore, we need to forget the fact that the preceding eKeyDown was
   // consumed right now.
   // NOTE: On Windows, eKeyPress may be fired without preceding eKeyDown if
   // IME or utility app sends WM_CHAR message.  So, if we don't forget it,
   // we'd consume unrelated eKeyPress events.
   else if (aEvent.mMessage == eKeyUp &&
            mPreviousConsumedKeyDownCode.isSome() &&
            aEvent.mCodeNameIndex == mPreviousConsumedKeyDownCode.value()) {
     mPreviousConsumedKeyDownCode.reset();
   }

   if (localEvent.mFlags.mIsSuppressedOrDelayed) {
     localEvent.PreventDefault();
   }

   // If the event's default isn't prevented but the status is no default,
   // That means that the event was consumed by EventStateManager or something
   // which is not a usual event handler.  In such case, prevent its default
   // as a default handler.  For example, when an eKeyPress event matches
   // with a content accesskey, and it's executed, preventDefault() of the
   // event won't be called but the status is set to "no default".  Then,
   // the event shouldn't be handled by nsMenuBarListener in the main process.
   if (!localEvent.DefaultPrevented() &&
       status == nsEventStatus_eConsumeNoDefault) {
     localEvent.PreventDefault();
   }

   MOZ_DIAGNOSTIC_ASSERT(!localEvent.PropagationStopped());
 }
 // The keyboard event which we ignore should not be handled in the main
 // process for shortcut key handling.  For notifying if we skipped it, we can
 // use "stop propagation" flag here because it must be cleared by
 // `EventTargetChainItem` if we've dispatched it.
 else {
   localEvent.StopPropagation();
 }

 // If we don't need to send a rely for the given keyboard event, we do nothing
 // anymore here.
 if (!aEvent.WantReplyFromContentProcess()) {
   return IPC_OK();
 }

 // This is an ugly hack, mNoRemoteProcessDispatch is set to true when the
 // event's PreventDefault() or StopScrollProcessForwarding() is called.
 // And then, it'll be checked by ParamTraits<mozilla::WidgetEvent>::Write()
 // whether the event is being sent to remote process unexpectedly.
 // However, unfortunately, it cannot check the destination.  Therefore,
 // we need to clear the flag explicitly here because ParamTraits should
 // keep checking the flag for avoiding regression.
 localEvent.mFlags.mNoRemoteProcessDispatch = false;
 SendReplyKeyEvent(localEvent, aUUID);

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPriorityRealKeyEvent(
   const WidgetKeyboardEvent& aEvent, const nsID& aUUID) {
 return RecvRealKeyEvent(aEvent, aUUID);
}

mozilla::ipc::IPCResult BrowserChild::RecvCompositionEvent(
   const WidgetCompositionEvent& aEvent) {
 WidgetCompositionEvent localEvent(aEvent);
 localEvent.mWidget = mPuppetWidget;
 DispatchWidgetEventViaAPZ(localEvent);
 (void)SendOnEventNeedingAckHandled(aEvent.mMessage,
                                    localEvent.mCompositionId);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPriorityCompositionEvent(
   const WidgetCompositionEvent& aEvent) {
 return RecvCompositionEvent(aEvent);
}

mozilla::ipc::IPCResult BrowserChild::RecvSelectionEvent(
   const WidgetSelectionEvent& aEvent) {
 WidgetSelectionEvent localEvent(aEvent);
 localEvent.mWidget = mPuppetWidget;
 DispatchWidgetEventViaAPZ(localEvent);
 (void)SendOnEventNeedingAckHandled(aEvent.mMessage, 0u);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPrioritySelectionEvent(
   const WidgetSelectionEvent& aEvent) {
 return RecvSelectionEvent(aEvent);
}

mozilla::ipc::IPCResult BrowserChild::RecvSimpleContentCommandEvent(
   const EventMessage& aMessage) {
 WidgetContentCommandEvent localEvent(true, aMessage, mPuppetWidget);
 DispatchWidgetEventViaAPZ(localEvent);
 (void)SendOnEventNeedingAckHandled(aMessage, 0u);
 return IPC_OK();
}

mozilla::ipc::IPCResult
BrowserChild::RecvNormalPrioritySimpleContentCommandEvent(
   const EventMessage& aMessage) {
 return RecvSimpleContentCommandEvent(aMessage);
}

mozilla::ipc::IPCResult BrowserChild::RecvInsertText(
   const nsAString& aStringToInsert) {
 // Use normal event path to reach focused document.
 WidgetContentCommandEvent localEvent(true, eContentCommandInsertText,
                                      mPuppetWidget);
 localEvent.mString = Some(nsString(aStringToInsert));
 DispatchWidgetEventViaAPZ(localEvent);
 (void)SendOnEventNeedingAckHandled(eContentCommandInsertText, 0u);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPriorityInsertText(
   const nsAString& aStringToInsert) {
 return RecvInsertText(aStringToInsert);
}

mozilla::ipc::IPCResult BrowserChild::RecvReplaceText(
   const nsString& aReplaceSrcString, const nsString& aStringToInsert,
   uint32_t aOffset, bool aPreventSetSelection) {
 // Use normal event path to reach focused document.
 WidgetContentCommandEvent localEvent(true, eContentCommandReplaceText,
                                      mPuppetWidget);
 localEvent.mString = Some(aStringToInsert);
 localEvent.mSelection.mReplaceSrcString = aReplaceSrcString;
 localEvent.mSelection.mOffset = aOffset;
 localEvent.mSelection.mPreventSetSelection = aPreventSetSelection;
 DispatchWidgetEventViaAPZ(localEvent);
 (void)SendOnEventNeedingAckHandled(eContentCommandReplaceText, 0u);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvNormalPriorityReplaceText(
   const nsString& aReplaceSrcString, const nsString& aStringToInsert,
   uint32_t aOffset, bool aPreventSetSelection) {
 return RecvReplaceText(aReplaceSrcString, aStringToInsert, aOffset,
                        aPreventSetSelection);
}

mozilla::ipc::IPCResult BrowserChild::RecvPasteTransferable(
   const IPCTransferable& aTransferable) {
 nsresult rv;
 nsCOMPtr<nsITransferable> trans =
     do_CreateInstance("@mozilla.org/widget/transferable;1", &rv);
 NS_ENSURE_SUCCESS(rv, IPC_OK());
 trans->Init(nullptr);

 rv = nsContentUtils::IPCTransferableToTransferable(
     aTransferable, true /* aAddDataFlavor */, trans,
     false /* aFilterUnknownFlavors */);
 NS_ENSURE_SUCCESS(rv, IPC_OK());

 nsCOMPtr<nsIDocShell> ourDocShell = do_GetInterface(WebNavigation());
 if (NS_WARN_IF(!ourDocShell)) {
   return IPC_OK();
 }

 RefPtr<nsCommandParams> params = new nsCommandParams();
 rv = params->SetISupports("transferable", trans);
 NS_ENSURE_SUCCESS(rv, IPC_OK());

 ourDocShell->DoCommandWithParams("cmd_pasteTransferable", params);
 return IPC_OK();
}

#ifdef ACCESSIBILITY
a11y::PDocAccessibleChild* BrowserChild::AllocPDocAccessibleChild(
   PDocAccessibleChild*, const uint64_t&,
   const MaybeDiscardedBrowsingContext&) {
 MOZ_ASSERT(false, "should never call this!");
 return nullptr;
}

bool BrowserChild::DeallocPDocAccessibleChild(
   a11y::PDocAccessibleChild* aChild) {
 delete static_cast<mozilla::a11y::DocAccessibleChild*>(aChild);
 return true;
}
#endif

RefPtr<VsyncMainChild> BrowserChild::GetVsyncChild() {
 // Initializing VsyncMainChild here turns on per-BrowserChild Vsync for a
 // given platform. Note: this only makes sense if nsWindow returns a
 // window-specific VsyncSource.
#if defined(MOZ_WAYLAND)
 if (IsWaylandEnabled()) {
   if (auto* actor = static_cast<VsyncMainChild*>(
           LoneManagedOrNullAsserts(ManagedPVsyncChild()))) {
     return actor;
   }
   auto actor = MakeRefPtr<VsyncMainChild>();
   if (!SendPVsyncConstructor(actor)) {
     return nullptr;
   }
   return actor;
 }
#endif
 return nullptr;
}

mozilla::ipc::IPCResult BrowserChild::RecvLoadRemoteScript(
   const nsAString& aURL, const bool& aRunInGlobalScope) {
 if (!InitBrowserChildMessageManager())
   // This can happen if we're half-destroyed.  It's not a fatal
   // error.
   return IPC_OK();

 JS::Rooted<JSObject*> mm(RootingCx(),
                          mBrowserChildMessageManager->GetOrCreateWrapper());
 if (!mm) {
   // This can happen if we're half-destroyed.  It's not a fatal error.
   return IPC_OK();
 }

 LoadScriptInternal(mm, aURL, !aRunInGlobalScope);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvAsyncMessage(
   const nsAString& aMessage, const ClonedMessageData& aData) {
 AUTO_PROFILER_LABEL_DYNAMIC_LOSSY_NSSTRING("BrowserChild::RecvAsyncMessage",
                                            OTHER, aMessage);
 MMPrinter::Print("BrowserChild::RecvAsyncMessage", aMessage, aData);

 if (!mBrowserChildMessageManager) {
   return IPC_OK();
 }

 RefPtr<nsFrameMessageManager> mm =
     mBrowserChildMessageManager->GetMessageManager();

 // We should have a message manager if the global is alive, but it
 // seems sometimes we don't.  Assert in aurora/nightly, but don't
 // crash in release builds.
 MOZ_DIAGNOSTIC_ASSERT(mm);
 if (!mm) {
   return IPC_OK();
 }

 JS::Rooted<JSObject*> kungFuDeathGrip(
     dom::RootingCx(), mBrowserChildMessageManager->GetWrapper());
 StructuredCloneData data;
 UnpackClonedMessageData(aData, data);
 mm->ReceiveMessage(static_cast<EventTarget*>(mBrowserChildMessageManager),
                    nullptr, aMessage, false, &data, nullptr, IgnoreErrors());
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvSwappedWithOtherRemoteLoader(
   const IPCTabContext& aContext) {
 nsCOMPtr<nsIDocShell> ourDocShell = do_GetInterface(WebNavigation());
 if (NS_WARN_IF(!ourDocShell)) {
   return IPC_OK();
 }

 nsCOMPtr<nsPIDOMWindowOuter> ourWindow = ourDocShell->GetWindow();
 if (NS_WARN_IF(!ourWindow)) {
   return IPC_OK();
 }

 RefPtr<nsDocShell> docShell = static_cast<nsDocShell*>(ourDocShell.get());

 nsCOMPtr<EventTarget> ourEventTarget = nsGlobalWindowOuter::Cast(ourWindow);

 docShell->SetInFrameSwap(true);

 nsContentUtils::FirePageShowEventForFrameLoaderSwap(
     ourDocShell, ourEventTarget, false, true);
 nsContentUtils::FirePageHideEventForFrameLoaderSwap(ourDocShell,
                                                     ourEventTarget, true);

 // Owner content type may have changed, so store the possibly updated context
 // and notify others.
 MaybeInvalidTabContext maybeContext(aContext);
 if (!maybeContext.IsValid()) {
   NS_ERROR(nsPrintfCString("Received an invalid TabContext from "
                            "the parent process. (%s)",
                            maybeContext.GetInvalidReason())
                .get());
   MOZ_CRASH("Invalid TabContext received from the parent process.");
 }

 if (!UpdateTabContextAfterSwap(maybeContext.GetTabContext())) {
   MOZ_CRASH("Update to TabContext after swap was denied.");
 }

 // Ignore previous value of mTriedBrowserInit since owner content has changed.
 mTriedBrowserInit = true;

 nsContentUtils::FirePageShowEventForFrameLoaderSwap(
     ourDocShell, ourEventTarget, true, true);

 docShell->SetInFrameSwap(false);

 // This is needed to get visibility state right in cases when we swapped a
 // visible tab (foreground in visible window) with a non-visible tab.
 if (RefPtr<Document> doc = docShell->GetDocument()) {
   doc->UpdateVisibilityState();
 }

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvHandleAccessKey(
   const WidgetKeyboardEvent& aEvent, nsTArray<uint32_t>&& aCharCodes) {
 nsCOMPtr<Document> document(GetTopLevelDocument());
 RefPtr<nsPresContext> pc = document->GetPresContext();
 if (pc) {
   if (!pc->EventStateManager()->HandleAccessKey(
           &(const_cast<WidgetKeyboardEvent&>(aEvent)), pc, aCharCodes)) {
     // If no accesskey was found, inform the parent so that accesskeys on
     // menus can be handled.
     WidgetKeyboardEvent localEvent(aEvent);
     localEvent.mWidget = mPuppetWidget;
     SendAccessKeyNotHandled(localEvent);
   }
 }

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvPrintPreview(
   const PrintData& aPrintData, const MaybeDiscardedBrowsingContext& aSourceBC,
   PrintPreviewResolver&& aCallback) {
#ifdef NS_PRINTING
 // If we didn't succeed in passing off ownership of aCallback, then something
 // went wrong.
 auto sendCallbackError = MakeScopeExit([&] {
   if (aCallback) {
     // signal error
     aCallback(PrintPreviewResultInfo(0, 0, false, false, false, {}, {}, {}));
   }
 });

 if (NS_WARN_IF(aSourceBC.IsDiscarded())) {
   return IPC_OK();
 }

 RefPtr<nsGlobalWindowOuter> sourceWindow;
 if (!aSourceBC.IsNull()) {
   sourceWindow = nsGlobalWindowOuter::Cast(aSourceBC.get()->GetDOMWindow());
   if (NS_WARN_IF(!sourceWindow)) {
     return IPC_OK();
   }
 } else {
   nsCOMPtr<nsPIDOMWindowOuter> ourWindow = do_GetInterface(WebNavigation());
   if (NS_WARN_IF(!ourWindow)) {
     return IPC_OK();
   }
   sourceWindow = nsGlobalWindowOuter::Cast(ourWindow);
 }

 RefPtr<nsIPrintSettings> printSettings;
 nsCOMPtr<nsIPrintSettingsService> printSettingsSvc =
     do_GetService("@mozilla.org/gfx/printsettings-service;1");
 if (NS_WARN_IF(!printSettingsSvc)) {
   return IPC_OK();
 }
 printSettingsSvc->CreateNewPrintSettings(getter_AddRefs(printSettings));
 if (NS_WARN_IF(!printSettings)) {
   return IPC_OK();
 }
 printSettingsSvc->DeserializeToPrintSettings(aPrintData, printSettings);

 nsCOMPtr<nsIDocShell> docShellToCloneInto;
 if (!aSourceBC.IsNull()) {
   docShellToCloneInto = do_GetInterface(WebNavigation());
   if (NS_WARN_IF(!docShellToCloneInto)) {
     return IPC_OK();
   }
 }

 sourceWindow->Print(printSettings,
                     /* aRemotePrintJob = */ nullptr,
                     /* aListener = */ nullptr, docShellToCloneInto,
                     nsGlobalWindowOuter::IsPreview::Yes,
                     nsGlobalWindowOuter::IsForWindowDotPrint::No,
                     std::move(aCallback), nullptr, IgnoreErrors());
#endif
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvExitPrintPreview() {
#ifdef NS_PRINTING
 nsCOMPtr<nsIWebBrowserPrint> webBrowserPrint =
     do_GetInterface(ToSupports(WebNavigation()));
 if (NS_WARN_IF(!webBrowserPrint)) {
   return IPC_OK();
 }
 webBrowserPrint->ExitPrintPreview();
#endif
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::CommonPrint(
   const MaybeDiscardedBrowsingContext& aBc, const PrintData& aPrintData,
   RefPtr<BrowsingContext>* aCachedBrowsingContext) {
#ifdef NS_PRINTING
 if (NS_WARN_IF(aBc.IsNullOrDiscarded())) {
   return IPC_OK();
 }
 RefPtr<nsGlobalWindowOuter> outerWindow =
     nsGlobalWindowOuter::Cast(aBc.get()->GetDOMWindow());
 if (NS_WARN_IF(!outerWindow)) {
   return IPC_OK();
 }

 nsCOMPtr<nsIPrintSettingsService> printSettingsSvc =
     do_GetService("@mozilla.org/gfx/printsettings-service;1");
 if (NS_WARN_IF(!printSettingsSvc)) {
   return IPC_OK();
 }

 nsCOMPtr<nsIPrintSettings> printSettings;
 nsresult rv =
     printSettingsSvc->CreateNewPrintSettings(getter_AddRefs(printSettings));
 if (NS_WARN_IF(NS_FAILED(rv))) {
   return IPC_OK();
 }

 printSettingsSvc->DeserializeToPrintSettings(aPrintData, printSettings);
 {
   IgnoredErrorResult rv;
   RefPtr printJob = static_cast<RemotePrintJobChild*>(
       aPrintData.remotePrintJob().AsChild());
   outerWindow->Print(
       printSettings, printJob,
       /* aListener = */ nullptr,
       /* aWindowToCloneInto = */ nullptr, nsGlobalWindowOuter::IsPreview::No,
       nsGlobalWindowOuter::IsForWindowDotPrint::No,
       /* aPrintPreviewCallback = */ nullptr, aCachedBrowsingContext, rv);
   if (NS_WARN_IF(rv.Failed())) {
     return IPC_OK();
   }
 }
#endif
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvPrint(
   const MaybeDiscardedBrowsingContext& aBc, const PrintData& aPrintData,
   bool aReturnStaticClone, PrintResolver&& aResolve) {
#ifdef NS_PRINTING
 RefPtr<BrowsingContext> browsingContext;
 auto result = CommonPrint(aBc, aPrintData,
                           aReturnStaticClone ? &browsingContext : nullptr);
 aResolve(browsingContext);
 return result;
#else
 aResolve(nullptr);
 return IPC_OK();
#endif
}

mozilla::ipc::IPCResult BrowserChild::RecvPrintClonedPage(
   const MaybeDiscardedBrowsingContext& aBc, const PrintData& aPrintData,
   const MaybeDiscardedBrowsingContext& aClonedBc) {
#ifdef NS_PRINTING
 if (aClonedBc.IsNullOrDiscarded()) {
   return IPC_OK();
 }
 RefPtr<BrowsingContext> clonedBc = aClonedBc.get();
 return CommonPrint(aBc, aPrintData, &clonedBc);
#else
 return IPC_OK();
#endif
}

mozilla::ipc::IPCResult BrowserChild::RecvDestroyPrintClone(
   const MaybeDiscardedBrowsingContext& aCachedPage) {
#ifdef NS_PRINTING
 if (aCachedPage) {
   RefPtr<nsPIDOMWindowOuter> window = aCachedPage->GetDOMWindow();
   if (NS_WARN_IF(!window)) {
     return IPC_OK();
   }
   window->Close();
 }
#endif
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvUpdateNativeWindowHandle(
   const uintptr_t& aNewHandle) {
#if defined(XP_WIN) && defined(ACCESSIBILITY)
 mNativeWindowHandle = aNewHandle;
 return IPC_OK();
#else
 return IPC_FAIL_NO_REASON(this);
#endif
}

mozilla::ipc::IPCResult BrowserChild::RecvDestroy() {
 MOZ_ASSERT(!mDestroyed);
 mDestroyed = true;

 nsTArray<PContentPermissionRequestChild*> childArray =
     nsContentPermissionUtils::GetContentPermissionRequestChildById(
         GetTabId());

 // Need to close undeleted ContentPermissionRequestChilds before tab is
 // closed.
 for (auto& permissionRequestChild : childArray) {
   auto* child = static_cast<RemotePermissionRequest*>(permissionRequestChild);
   child->Destroy();
 }

 if (mBrowserChildMessageManager) {
   // Message handlers are called from the event loop, so it better be safe to
   // run script.
   MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
   mBrowserChildMessageManager->DispatchTrustedEvent(u"unload"_ns);
 }

 nsCOMPtr<nsIObserverService> observerService =
     mozilla::services::GetObserverService();

 observerService->RemoveObserver(this, BEFORE_FIRST_PAINT);

 // XXX what other code in ~BrowserChild() should we be running here?
 DestroyWindow();

 // Bounce through the event loop once to allow any delayed teardown runnables
 // that were just generated to have a chance to run.
 nsCOMPtr<nsIRunnable> deleteRunnable = new DelayedDeleteRunnable(this);
 MOZ_ALWAYS_SUCCEEDS(NS_DispatchToCurrentThread(deleteRunnable));

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvRenderLayers(const bool& aEnabled) {
 auto clearPaintWhileInterruptingJS = MakeScopeExit([&] {
   // We might force a paint, or we might already have painted and this is a
   // no-op. In either case, once we exit this scope, we need to alert the
   // ProcessHangMonitor that we've finished responding to what might have
   // been a request to force paint. This is so that the BackgroundHangMonitor
   // for force painting can be made to wait again.
   if (aEnabled) {
     ProcessHangMonitor::ClearPaintWhileInterruptingJS();
   }
 });

 if (aEnabled) {
   ProcessHangMonitor::MaybeStartPaintWhileInterruptingJS();
 }

 mRenderLayers = aEnabled;
 const bool wasVisible = IsVisible();

 UpdateVisibility();

 // If we just became visible, try to trigger a paint as soon as possible.
 const bool becameVisible = !wasVisible && IsVisible();
 if (!becameVisible) {
   return IPC_OK();
 }

 nsCOMPtr<nsIDocShell> docShell = do_GetInterface(WebNavigation());
 if (!docShell) {
   return IPC_OK();
 }

 // We don't use BrowserChildBase::GetPresShell() here because that would
 // create a content viewer if one doesn't exist yet. Creating a content
 // viewer can cause JS to run, which we want to avoid.
 // nsIDocShell::GetPresShell returns null if no content viewer exists yet.
 RefPtr<PresShell> presShell = docShell->GetPresShell();
 if (!presShell) {
   return IPC_OK();
 }

 if (nsIFrame* root = presShell->GetRootFrame()) {
   root->SchedulePaint();
 }

 // If we need to repaint, let's do that right away. No sense waiting until
 // we get back to the event loop again. We suppress the display port so
 // that we only paint what's visible. This ensures that the tab we're
 // switching to paints as quickly as possible.
 presShell->SuppressDisplayport(true);
 if (nsContentUtils::IsSafeToRunScript()) {
   WebWidget()->PaintNowIfNeeded();
 } else {
   // NOTE: We want to call in even without a root frame (we might paint the
   // canvas background in that case).
   presShell->PaintAndRequestComposite(presShell->GetRootFrame(),
                                       mPuppetWidget->GetWindowRenderer(),
                                       PaintFlags::None);
 }
 presShell->SuppressDisplayport(false);
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvNavigateByKey(
   const bool& aForward, const bool& aForDocumentNavigation) {
 nsFocusManager* fm = nsFocusManager::GetFocusManager();
 if (!fm) {
   return IPC_OK();
 }

 RefPtr<Element> result;
 nsCOMPtr<nsPIDOMWindowOuter> window = do_GetInterface(WebNavigation());

 // Move to the first or last document.
 {
   uint32_t type =
       aForward
           ? (aForDocumentNavigation
                  ? static_cast<uint32_t>(nsIFocusManager::MOVEFOCUS_FIRSTDOC)
                  : static_cast<uint32_t>(nsIFocusManager::MOVEFOCUS_FIRST))
           : (aForDocumentNavigation
                  ? static_cast<uint32_t>(nsIFocusManager::MOVEFOCUS_LASTDOC)
                  : static_cast<uint32_t>(nsIFocusManager::MOVEFOCUS_LAST));
   uint32_t flags = nsIFocusManager::FLAG_BYKEY;
   if (aForward || aForDocumentNavigation) {
     flags |= nsIFocusManager::FLAG_NOSCROLL;
   }
   fm->MoveFocus(window, nullptr, type, flags, getter_AddRefs(result));
 }

 // No valid root element was found, so move to the first focusable element.
 if (!result && aForward && !aForDocumentNavigation) {
   fm->MoveFocus(window, nullptr, nsIFocusManager::MOVEFOCUS_FIRST,
                 nsIFocusManager::FLAG_BYKEY, getter_AddRefs(result));
 }

 SendRequestFocus(false, CallerType::System);
 return IPC_OK();
}

bool BrowserChild::InitBrowserChildMessageManager() {
 mShouldSendWebProgressEventsToParent = true;

 if (!mBrowserChildMessageManager) {
   nsCOMPtr<nsPIDOMWindowOuter> window = do_GetInterface(WebNavigation());
   NS_ENSURE_TRUE(window, false);
   nsCOMPtr<EventTarget> chromeHandler = window->GetChromeEventHandler();
   NS_ENSURE_TRUE(chromeHandler, false);

   RefPtr<BrowserChildMessageManager> scope = mBrowserChildMessageManager =
       new BrowserChildMessageManager(this);

   MOZ_ALWAYS_TRUE(nsMessageManagerScriptExecutor::Init());

   nsCOMPtr<nsPIWindowRoot> root = do_QueryInterface(chromeHandler);
   if (NS_WARN_IF(!root)) {
     mBrowserChildMessageManager = nullptr;
     return false;
   }
   root->SetParentTarget(scope);
 }

 if (!mTriedBrowserInit) {
   mTriedBrowserInit = true;
 }

 return true;
}

void BrowserChild::InitRenderingState(
   const TextureFactoryIdentifier& aTextureFactoryIdentifier,
   const layers::LayersId& aLayersId,
   const CompositorOptions& aCompositorOptions) {
 mPuppetWidget->InitIMEState();

 MOZ_ASSERT(aLayersId.IsValid());
 mTextureFactoryIdentifier = aTextureFactoryIdentifier;

 // Pushing layers transactions directly to a separate
 // compositor context.
 PCompositorBridgeChild* compositorChild = CompositorBridgeChild::Get();
 if (!compositorChild) {
   mLayersConnected = Some(false);
   NS_WARNING("failed to get CompositorBridgeChild instance");
   return;
 }

 mCompositorOptions = Some(aCompositorOptions);

 if (aLayersId.IsValid()) {
   StaticMutexAutoLock lock(sBrowserChildrenMutex);

   if (!sBrowserChildren) {
     sBrowserChildren = new BrowserChildMap;
   }
   MOZ_ASSERT(!sBrowserChildren->Contains(uint64_t(aLayersId)));
   sBrowserChildren->InsertOrUpdate(uint64_t(aLayersId), this);
   mLayersId = aLayersId;
 }

 // Depending on timing, we might paint too early and fall back to basic
 // layers. CreateRemoteLayerManager will destroy us if we manage to get a
 // remote layer manager though, so that's fine.
 MOZ_ASSERT(!mPuppetWidget->HasWindowRenderer() ||
            mPuppetWidget->GetWindowRenderer()->GetBackendType() ==
                layers::LayersBackend::LAYERS_NONE);
 bool success = false;
 if (mLayersConnected == Some(true)) {
   success = CreateRemoteLayerManager(compositorChild);
 }

 if (success) {
   MOZ_ASSERT(mLayersConnected == Some(true));
   // Succeeded to create "remote" layer manager
   ImageBridgeChild::IdentifyCompositorTextureHost(mTextureFactoryIdentifier);
   gfx::VRManagerChild::IdentifyTextureHost(mTextureFactoryIdentifier);
   InitAPZState();
 } else {
   mLayersConnected = Some(false);
 }

 nsCOMPtr<nsIObserverService> observerService =
     mozilla::services::GetObserverService();

 if (observerService) {
   observerService->AddObserver(this, BEFORE_FIRST_PAINT, false);
 }
}

bool BrowserChild::CreateRemoteLayerManager(
   mozilla::layers::PCompositorBridgeChild* aCompositorChild) {
 MOZ_ASSERT(aCompositorChild);

 return mPuppetWidget->CreateRemoteLayerManager(
     [&](WebRenderLayerManager* aLayerManager) -> bool {
       nsCString error;
       return aLayerManager->Initialize(aCompositorChild,
                                        wr::AsPipelineId(mLayersId),
                                        &mTextureFactoryIdentifier, error);
     });
}

void BrowserChild::InitAPZState() {
 if (!mCompositorOptions->UseAPZ()) {
   return;
 }
 auto* cbc = CompositorBridgeChild::Get();

 // Initialize the ApzcTreeManager. This takes multiple casts because of ugly
 // multiple inheritance.
 PAPZCTreeManagerChild* baseProtocol =
     cbc->SendPAPZCTreeManagerConstructor(mLayersId);
 if (!baseProtocol) {
   MOZ_ASSERT(false,
              "Allocating a TreeManager should not fail with APZ enabled");
   return;
 }
 APZCTreeManagerChild* derivedProtocol =
     static_cast<APZCTreeManagerChild*>(baseProtocol);

 mApzcTreeManager = RefPtr<IAPZCTreeManager>(derivedProtocol);

 // Initialize the GeckoContentController for this tab. We don't hold a
 // reference because we don't need it. The ContentProcessController will hold
 // a reference to the tab, and will be destroyed by the compositor or ipdl
 // during destruction.
 RefPtr<GeckoContentController> contentController =
     new ContentProcessController(this);
 APZChild* apzChild = new APZChild(contentController);
 cbc->SendPAPZConstructor(apzChild, mLayersId);
}

IPCResult BrowserChild::RecvUpdateEffects(const EffectsInfo& aEffects) {
 bool needInvalidate = false;
 if (mEffectsInfo.IsVisible() && aEffects.IsVisible() &&
     mEffectsInfo != aEffects) {
   // If we are staying visible and either the visrect or scale changed we need
   // to invalidate
   needInvalidate = true;
 }

 mEffectsInfo = aEffects;
 UpdateVisibility();

 if (needInvalidate) {
   if (nsCOMPtr<nsIDocShell> docShell = do_GetInterface(WebNavigation())) {
     // We don't use BrowserChildBase::GetPresShell() here because that would
     // create a content viewer if one doesn't exist yet. Creating a content
     // viewer can cause JS to run, which we want to avoid.
     // nsIDocShell::GetPresShell returns null if no content viewer exists yet.
     if (RefPtr<PresShell> presShell = docShell->GetPresShell()) {
       if (nsIFrame* root = presShell->GetRootFrame()) {
         root->InvalidateFrame();
       }
     }
   }
 }

 return IPC_OK();
}

bool BrowserChild::IsVisible() {
 return mPuppetWidget && mPuppetWidget->IsVisible();
}

void BrowserChild::UpdateVisibility() {
 const bool shouldBeVisible = [&] {
   // If we're known to be visibility: hidden / display: none, just return
   // false here, we're pretty sure we don't want to be considered visible
   // here.
   if (mBrowsingContext && mBrowsingContext->IsUnderHiddenEmbedderElement()) {
     return false;
   }
   // If we're explicitly told not to render layers, we're also invisible.
   if (!mRenderLayers) {
     return false;
   }
   if (!mIsTopLevel) {
     // For OOP iframes, include viewport visibility.
     if (!mEffectsInfo.IsVisible()) {
       return false;
     }
     // Also include activeness, unless we're artificially preserving layers.
     // An alternative to this would be to propagate mRenderLayers from the
     // parent, perhaps, so that it applies to the whole tree...
     if (!mIsPreservingLayers && mBrowsingContext &&
         !mBrowsingContext->IsActive()) {
       return false;
     }
   }
   return true;
 }();

 const bool isVisible = IsVisible();
 if (shouldBeVisible == isVisible) {
   return;
 }
 if (shouldBeVisible) {
   MakeVisible();
 } else {
   MakeHidden();
 }
}

void BrowserChild::MakeVisible() {
 if (IsVisible()) {
   return;
 }

 if (mPuppetWidget) {
   mPuppetWidget->Show(true);
 }

 PresShellActivenessMaybeChanged();
}

void BrowserChild::MakeHidden() {
 if (!IsVisible()) {
   return;
 }

 // Due to the nested event loop in ContentChild::ProvideWindowCommon,
 // it's possible to be told to become hidden before we're finished
 // setting up a layer manager. We should skip clearing cached layers
 // in that case, since doing so might accidentally put is into
 // BasicLayers mode.
 if (mPuppetWidget) {
   if (mPuppetWidget->HasWindowRenderer()) {
     ClearCachedResources();
   }
   mPuppetWidget->Show(false);
 }

 PresShellActivenessMaybeChanged();
}

IPCResult BrowserChild::RecvPreserveLayers(bool aPreserve) {
 mIsPreservingLayers = aPreserve;

 UpdateVisibility();
 PresShellActivenessMaybeChanged();

 return IPC_OK();
}

void BrowserChild::PresShellActivenessMaybeChanged() {
 // We don't use BrowserChildBase::GetPresShell() here because that would
 // create a content viewer if one doesn't exist yet. Creating a content
 // viewer can cause JS to run, which we want to avoid.
 // nsIDocShell::GetPresShell returns null if no content viewer exists yet.
 //
 // When this method is called we don't want to go through the browsing context
 // because we don't want to change the visibility state of the document, which
 // has side effects like firing events to content, unblocking media playback,
 // unthrottling timeouts... PresShell activeness has a lot less side effects.
 nsCOMPtr<nsIDocShell> docShell = do_GetInterface(WebNavigation());
 if (!docShell) {
   return;
 }
 RefPtr<PresShell> presShell = docShell->GetPresShell();
 if (!presShell) {
   return;
 }
 presShell->ActivenessMaybeChanged();
}

NS_IMETHODIMP
BrowserChild::GetMessageManager(ContentFrameMessageManager** aResult) {
 RefPtr<ContentFrameMessageManager> mm(mBrowserChildMessageManager);
 mm.forget(aResult);
 return *aResult ? NS_OK : NS_ERROR_FAILURE;
}

void BrowserChild::SendRequestFocus(bool aCanFocus, CallerType aCallerType) {
 nsFocusManager* fm = nsFocusManager::GetFocusManager();
 if (!fm) {
   return;
 }

 nsCOMPtr<nsPIDOMWindowOuter> window = do_GetInterface(WebNavigation());
 if (!window) {
   return;
 }

 BrowsingContext* focusedBC = fm->GetFocusedBrowsingContext();
 if (focusedBC == window->GetBrowsingContext()) {
   // BrowsingContext has the focus already, do not request again.
   return;
 }

 PBrowserChild::SendRequestFocus(aCanFocus, aCallerType);
}

NS_IMETHODIMP
BrowserChild::GetTabId(uint64_t* aId) {
 *aId = GetTabId();
 return NS_OK;
}

NS_IMETHODIMP
BrowserChild::GetChromeOuterWindowID(uint64_t* aId) {
 *aId = ChromeOuterWindowID();
 return NS_OK;
}

bool BrowserChild::DoSendBlockingMessage(
   const nsAString& aMessage, StructuredCloneData& aData,
   nsTArray<UniquePtr<StructuredCloneData>>* aRetVal) {
 ClonedMessageData data;
 if (!BuildClonedMessageData(aData, data)) {
   return false;
 }
 return SendSyncMessage(PromiseFlatString(aMessage), data, aRetVal);
}

nsresult BrowserChild::DoSendAsyncMessage(const nsAString& aMessage,
                                         StructuredCloneData& aData) {
 ClonedMessageData data;
 if (!BuildClonedMessageData(aData, data)) {
   return NS_ERROR_DOM_DATA_CLONE_ERR;
 }
 if (!SendAsyncMessage(PromiseFlatString(aMessage), data)) {
   return NS_ERROR_UNEXPECTED;
 }
 return NS_OK;
}

/* static */
nsTArray<RefPtr<BrowserChild>> BrowserChild::GetAll() {
 StaticMutexAutoLock lock(sBrowserChildrenMutex);

 if (!sBrowserChildren) {
   return {};
 }

 return ToTArray<nsTArray<RefPtr<BrowserChild>>>(sBrowserChildren->Values());
}

BrowserChild* BrowserChild::GetFrom(PresShell* aPresShell) {
 Document* doc = aPresShell->GetDocument();
 if (!doc) {
   return nullptr;
 }
 nsCOMPtr<nsIDocShell> docShell(doc->GetDocShell());
 return GetFrom(docShell);
}

BrowserChild* BrowserChild::GetFrom(layers::LayersId aLayersId) {
 StaticMutexAutoLock lock(sBrowserChildrenMutex);
 if (!sBrowserChildren) {
   return nullptr;
 }
 return sBrowserChildren->Get(uint64_t(aLayersId));
}

void BrowserChild::DidComposite(mozilla::layers::TransactionId aTransactionId,
                               const TimeStamp& aCompositeStart,
                               const TimeStamp& aCompositeEnd) {
 MOZ_ASSERT(mPuppetWidget);
 RefPtr<WebRenderLayerManager> lm =
     mPuppetWidget->GetWindowRenderer()->AsWebRender();
 MOZ_ASSERT(lm);

 if (lm) {
   lm->DidComposite(aTransactionId, aCompositeStart, aCompositeEnd);
 }
}

void BrowserChild::ClearCachedResources() {
 MOZ_ASSERT(mPuppetWidget);
 RefPtr<WebRenderLayerManager> lm =
     mPuppetWidget->GetWindowRenderer()->AsWebRender();
 if (lm) {
   lm->ClearCachedResources();
 }

 if (nsCOMPtr<Document> document = GetTopLevelDocument()) {
   nsPresContext* presContext = document->GetPresContext();
   if (presContext) {
     presContext->NotifyPaintStatusReset();
   }
 }
}

void BrowserChild::SchedulePaint() {
 nsCOMPtr<nsIDocShell> docShell = do_GetInterface(WebNavigation());
 if (!docShell) {
   return;
 }

 // We don't use BrowserChildBase::GetPresShell() here because that would
 // create a content viewer if one doesn't exist yet. Creating a content viewer
 // can cause JS to run, which we want to avoid. nsIDocShell::GetPresShell
 // returns null if no content viewer exists yet.
 if (RefPtr<PresShell> presShell = docShell->GetPresShell()) {
   if (nsIFrame* root = presShell->GetRootFrame()) {
     root->SchedulePaint();
   }
 }
}

void SkipViewTransitionsAfterRenderingReset(Document& aDocument) {
 if (RefPtr<ViewTransition> transition = aDocument.GetActiveViewTransition()) {
   transition->SkipTransition(SkipTransitionReason::ResetRendering);
 }

 aDocument.EnumerateSubDocuments([&](Document& aSubDoc) {
   SkipViewTransitionsAfterRenderingReset(aSubDoc);
   return CallState::Continue;
 });
}

void BrowserChild::ReinitRendering() {
 MOZ_ASSERT(mLayersId.IsValid());

 if (RefPtr<Document> doc = GetTopLevelDocument()) {
   SkipViewTransitionsAfterRenderingReset(*doc);
 }

 // In some cases, like when we create a windowless browser,
 // RemoteLayerTreeOwner/BrowserChild is not connected to a compositor.
 if (mLayersConnectRequested.isNothing() ||
     mLayersConnectRequested == Some(false)) {
   return;
 }

 // Before we establish a new PLayerTransaction, we must connect our layer tree
 // id, CompositorBridge, and the widget compositor all together again.
 // Normally this happens in BrowserParent before BrowserChild is given
 // rendering information.
 //
 // In this case, we will send a sync message to our BrowserParent, which in
 // turn will send a sync message to the Compositor of the widget owning this
 // tab. This guarantees the correct association is in place before our
 // PLayerTransaction constructor message arrives on the cross-process
 // compositor bridge.
 CompositorOptions options;
 SendEnsureLayersConnected(&options);
 mCompositorOptions = Some(options);

 bool success = false;
 RefPtr<CompositorBridgeChild> cb = CompositorBridgeChild::Get();

 if (cb) {
   success = CreateRemoteLayerManager(cb);
 }

 if (!success) {
   NS_WARNING("failed to recreate layer manager");
   return;
 }

 mLayersConnected = Some(true);
 ImageBridgeChild::IdentifyCompositorTextureHost(mTextureFactoryIdentifier);
 gfx::VRManagerChild::IdentifyTextureHost(mTextureFactoryIdentifier);

 InitAPZState();
 if (nsCOMPtr<Document> doc = GetTopLevelDocument()) {
   doc->NotifyLayerManagerRecreated();
 }

 if (mRenderLayers) {
   SchedulePaint();
 }
}

void BrowserChild::ReinitRenderingForDeviceReset() {
 RefPtr<WebRenderLayerManager> lm =
     mPuppetWidget->GetWindowRenderer()->AsWebRender();
 if (lm) {
   lm->DoDestroy(/* aIsSync */ true);
 }

 // Proceed with destroying and recreating the layer manager.
 ReinitRendering();
}

NS_IMETHODIMP
BrowserChild::OnShowTooltip(int32_t aXCoords, int32_t aYCoords,
                           const nsAString& aTipText,
                           const nsAString& aTipDir) {
 nsString str(aTipText);
 nsString dir(aTipDir);
 SendShowTooltip(aXCoords, aYCoords, str, dir);
 return NS_OK;
}

NS_IMETHODIMP
BrowserChild::OnHideTooltip() {
 SendHideTooltip();
 return NS_OK;
}

void BrowserChild::NotifyJankedAnimations(
   const nsTArray<uint64_t>& aJankedAnimations) {
 MOZ_ASSERT(mPuppetWidget);
 RefPtr<WebRenderLayerManager> lm =
     mPuppetWidget->GetWindowRenderer()->AsWebRender();
 if (lm) {
   lm->UpdatePartialPrerenderedAnimations(aJankedAnimations);
 }
}

mozilla::ipc::IPCResult BrowserChild::RecvUIResolutionChanged(
   const float& aDpi, const int32_t& aRounding, const double& aScale) {
 const LayoutDeviceIntSize oldInnerSize = GetInnerSize();
 if (aDpi > 0) {
   mPuppetWidget->UpdateBackingScaleCache(aDpi, aRounding, aScale);
 }

 const LayoutDeviceIntSize innerSize = GetInnerSize();
 if (mHasValidInnerSize && oldInnerSize != innerSize) {
   // See RecvUpdateDimensions for the order of these operations.
   nsCOMPtr<nsIBaseWindow> baseWin = do_QueryInterface(WebNavigation());
   baseWin->SetPositionAndSize(0, 0, innerSize.width, innerSize.height,
                               nsIBaseWindow::eRepaint);

   const LayoutDeviceIntRect widgetRect(
       GetOuterRect().TopLeft() + mClientOffset + mChromeOffset, innerSize);
   mPuppetWidget->Resize(widgetRect / mPuppetWidget->GetDesktopToDeviceScale(),
                         true);
 }

 nsCOMPtr<Document> document(GetTopLevelDocument());
 RefPtr<nsPresContext> presContext =
     document ? document->GetPresContext() : nullptr;
 if (presContext) {
   presContext->UIResolutionChangedSync();
 }

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvTransparencyChanged(
   const bool& aIsTransparent) {
 mIsTransparent = aIsTransparent;
 SchedulePaint();
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvSafeAreaInsetsChanged(
   const mozilla::LayoutDeviceIntMargin& aSafeAreaInsets) {
 mPuppetWidget->UpdateSafeAreaInsets(aSafeAreaInsets);

 LayoutDeviceIntMargin currentSafeAreaInsets;
 // aSafeAreaInsets is for current screen. But we have to calculate safe insets
 // for content window.
 LayoutDeviceIntRect outerRect = GetOuterRect();
 RefPtr<Screen> screen = widget::ScreenManager::GetSingleton().ScreenForRect(
     RoundedToInt(outerRect / mPuppetWidget->GetDesktopToDeviceScale()));
 if (screen) {
   LayoutDeviceIntRect windowRect = outerRect + mClientOffset + mChromeOffset;
   currentSafeAreaInsets = nsContentUtils::GetWindowSafeAreaInsets(
       screen, aSafeAreaInsets, windowRect);
 }

 if (nsCOMPtr<Document> document = GetTopLevelDocument()) {
   if (nsPresContext* presContext = document->GetPresContext()) {
     presContext->SetSafeAreaInsets(currentSafeAreaInsets);
   }
 }

 // https://github.com/w3c/csswg-drafts/issues/4670
 // Actually we don't set this value on sub document. This behaviour is
 // same as Blink that safe area insets isn't set on sub document.

 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvAllowScriptsToClose() {
 nsCOMPtr<nsPIDOMWindowOuter> window = do_GetInterface(WebNavigation());
 if (window) {
   nsGlobalWindowOuter::Cast(window)->AllowScriptsToClose();
 }
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvReleaseAllPointerCapture() {
 PointerEventHandler::ReleaseAllPointerCapture();
 return IPC_OK();
}

mozilla::ipc::IPCResult BrowserChild::RecvReleasePointerLock() {
 PointerLockManager::Unlock("BrowserChild::RecvReleasePointerLock");
 return IPC_OK();
}

PPaymentRequestChild* BrowserChild::AllocPPaymentRequestChild() {
 MOZ_CRASH(
     "We should never be manually allocating PPaymentRequestChild actors");
 return nullptr;
}

bool BrowserChild::DeallocPPaymentRequestChild(PPaymentRequestChild* actor) {
 delete actor;
 return true;
}

LayoutDeviceIntSize BrowserChild::GetInnerSize() {
 return RoundedToInt(mUnscaledInnerSize * mPuppetWidget->GetDefaultScale());
};

Maybe<nsRect> BrowserChild::GetVisibleRect() const {
 if (mIsTopLevel) {
   // We are conservative about visible rects for top-level browsers to avoid
   // artifacts when resizing
   return Nothing();
 }
 return mEffectsInfo.mVisibleRect;
}

Maybe<LayoutDeviceRect>
BrowserChild::GetTopLevelViewportVisibleRectInSelfCoords() const {
 if (mIsTopLevel) {
   return Nothing();
 }

 if (!mChildToParentConversionMatrix) {
   // We have no way to tell this remote document visible rect right now.
   return Nothing();
 }

 Maybe<LayoutDeviceToLayoutDeviceMatrix4x4> inverse =
     mChildToParentConversionMatrix->MaybeInverse();
 if (!inverse) {
   return Nothing();
 }

 // Convert the remote document visible rect to the coordinate system of the
 // iframe document.
 Maybe<LayoutDeviceRect> rect = UntransformBy(
     *inverse,
     ViewAs<LayoutDevicePixel>(
         mTopLevelViewportVisibleRectInBrowserCoords,
         PixelCastJustification::ContentProcessIsLayerInUiProcess),
     LayoutDeviceRect::MaxIntRect());
 if (!rect) {
   return Nothing();
 }

 return rect;
}

LayoutDeviceIntRect BrowserChild::GetOuterRect() {
 return RoundedToInt(mUnscaledOuterRect * mPuppetWidget->GetDefaultScale());
}

void BrowserChild::PaintWhileInterruptingJS() {
 if (!IPCOpen() || !mPuppetWidget || !mPuppetWidget->HasWindowRenderer()) {
   // Don't bother doing anything now. Better to wait until we receive the
   // message on the PContent channel.
   return;
 }

 MOZ_DIAGNOSTIC_ASSERT(nsContentUtils::IsSafeToRunScript());
 nsAutoScriptBlocker scriptBlocker;
 RecvRenderLayers(/* aEnabled = */ true);
}

void BrowserChild::UnloadLayersWhileInterruptingJS() {
 if (!IPCOpen() || !mPuppetWidget || !mPuppetWidget->HasWindowRenderer()) {
   // Don't bother doing anything now. Better to wait until we receive the
   // message on the PContent channel.
   return;
 }

 MOZ_DIAGNOSTIC_ASSERT(nsContentUtils::IsSafeToRunScript());
 nsAutoScriptBlocker scriptBlocker;
 RecvRenderLayers(/* aEnabled = */ false);
}

nsresult BrowserChild::CanCancelContentJS(
   nsIRemoteTab::NavigationType aNavigationType, int32_t aNavigationIndex,
   nsIURI* aNavigationURI, int32_t aEpoch, bool* aCanCancel) {
 nsresult rv;
 *aCanCancel = false;

 if (aEpoch <= mCancelContentJSEpoch) {
   // The next page loaded before we got here, so we shouldn't try to cancel
   // the content JS.
   return NS_OK;
 }

 // If we have session history in the parent we've already performed
 // the checks following, so we can return early.
 if (mozilla::SessionHistoryInParent()) {
   *aCanCancel = true;
   return NS_OK;
 }

 nsCOMPtr<nsIDocShell> docShell = do_GetInterface(WebNavigation());
 nsCOMPtr<nsISHistory> history;
 if (docShell) {
   history = nsDocShell::Cast(docShell)->GetSessionHistory()->LegacySHistory();
 }

 if (!history) {
   return NS_ERROR_FAILURE;
 }

 int32_t current;
 rv = history->GetIndex(&current);
 NS_ENSURE_SUCCESS(rv, rv);

 if (current == -1) {
   // This tab has no history! Just return.
   return NS_OK;
 }

 nsCOMPtr<nsISHEntry> entry;
 rv = history->GetEntryAtIndex(current, getter_AddRefs(entry));
 NS_ENSURE_SUCCESS(rv, rv);

 nsCOMPtr<nsIURI> currentURI = entry->GetURI();
 if (!net::SchemeIsHttpOrHttps(currentURI) && !currentURI->SchemeIs("file")) {
   // Only cancel content JS for http(s) and file URIs. Other URIs are probably
   // internal and we should just let them run to completion.
   return NS_OK;
 }

 if (aNavigationType == nsIRemoteTab::NAVIGATE_BACK) {
   aNavigationIndex = current - 1;
 } else if (aNavigationType == nsIRemoteTab::NAVIGATE_FORWARD) {
   aNavigationIndex = current + 1;
 } else if (aNavigationType == nsIRemoteTab::NAVIGATE_URL) {
   if (!aNavigationURI) {
     return NS_ERROR_FAILURE;
   }

   if (aNavigationURI->SchemeIs("javascript")) {
     // "javascript:" URIs don't (necessarily) trigger navigation to a
     // different page, so don't allow the current page's JS to terminate.
     return NS_OK;
   }

   // If navigating directly to a URL (e.g. via hitting Enter in the location
   // bar), then we can cancel anytime the next URL is different from the
   // current, *excluding* the ref ("#").
   bool equals;
   rv = currentURI->EqualsExceptRef(aNavigationURI, &equals);
   NS_ENSURE_SUCCESS(rv, rv);
   *aCanCancel = !equals;
   return NS_OK;
 }
 // Note: aNavigationType may also be NAVIGATE_INDEX, in which case we don't
 // need to do anything special.

 int32_t delta = aNavigationIndex > current ? 1 : -1;
 for (int32_t i = current + delta; i != aNavigationIndex + delta; i += delta) {
   nsCOMPtr<nsISHEntry> nextEntry;
   // If `i` happens to be negative, this call will fail (which is what we
   // would want to happen).
   rv = history->GetEntryAtIndex(i, getter_AddRefs(nextEntry));
   NS_ENSURE_SUCCESS(rv, rv);

   nsCOMPtr<nsISHEntry> laterEntry = delta == 1 ? nextEntry : entry;
   nsCOMPtr<nsIURI> thisURI = entry->GetURI();
   nsCOMPtr<nsIURI> nextURI = nextEntry->GetURI();

   // If we changed origin and the load wasn't in a subframe, we know it was
   // a full document load, so we can cancel the content JS safely.
   if (!laterEntry->GetIsSubFrame()) {
     nsAutoCString thisHost;
     rv = thisURI->GetPrePath(thisHost);
     NS_ENSURE_SUCCESS(rv, rv);

     nsAutoCString nextHost;
     rv = nextURI->GetPrePath(nextHost);
     NS_ENSURE_SUCCESS(rv, rv);

     if (!thisHost.Equals(nextHost)) {
       *aCanCancel = true;
       return NS_OK;
     }
   }

   entry = nextEntry;
 }

 return NS_OK;
}

NS_IMETHODIMP BrowserChild::OnStateChange(nsIWebProgress* aWebProgress,
                                         nsIRequest* aRequest,
                                         uint32_t aStateFlags,
                                         nsresult aStatus) {
 if (!IPCOpen() || mDestroyed || !mShouldSendWebProgressEventsToParent) {
   return NS_OK;
 }

 // We shouldn't need to notify the parent of redirect state changes, since
 // with DocumentChannel that only happens when we switch to the real channel,
 // and that's an implementation detail that we can hide.
 if (aStateFlags & nsIWebProgressListener::STATE_IS_REDIRECTED_DOCUMENT) {
   return NS_OK;
 }

 // Our OnStateChange call must have provided the nsIDocShell which the source
 // comes from. We'll use this to locate the corresponding BrowsingContext in
 // the parent process.
 nsCOMPtr<nsIDocShell> docShell = do_QueryInterface(aWebProgress);
 if (!docShell) {
   MOZ_ASSERT_UNREACHABLE("aWebProgress is null or not a nsIDocShell?");
   return NS_ERROR_UNEXPECTED;
 }

 WebProgressData webProgressData;
 Maybe<WebProgressStateChangeData> stateChangeData;
 RequestData requestData;

 MOZ_TRY(PrepareProgressListenerData(aWebProgress, aRequest, webProgressData,
                                     requestData));

 RefPtr<BrowsingContext> browsingContext = docShell->GetBrowsingContext();
 if (browsingContext->IsTopContent()) {
   stateChangeData.emplace();

   stateChangeData->isNavigating() = docShell->GetIsNavigating();
   stateChangeData->mayEnableCharacterEncodingMenu() =
       docShell->GetMayEnableCharacterEncodingMenu();

   RefPtr<Document> document = browsingContext->GetExtantDocument();
   if (document && aStateFlags & nsIWebProgressListener::STATE_STOP) {
     document->GetContentType(stateChangeData->contentType());
     document->GetCharacterSet(stateChangeData->charset());
     stateChangeData->documentURI() = document->GetDocumentURIObject();
   } else {
     stateChangeData->contentType().SetIsVoid(true);
     stateChangeData->charset().SetIsVoid(true);
   }
 }

 (void)SendOnStateChange(webProgressData, requestData, aStateFlags, aStatus,
                         stateChangeData);

 return NS_OK;
}

NS_IMETHODIMP BrowserChild::OnProgressChange(nsIWebProgress* aWebProgress,
                                            nsIRequest* aRequest,
                                            int32_t aCurSelfProgress,
                                            int32_t aMaxSelfProgress,
                                            int32_t aCurTotalProgress,
                                            int32_t aMaxTotalProgress) {
 if (!IPCOpen() || mDestroyed || !mShouldSendWebProgressEventsToParent) {
   return NS_OK;
 }

 // FIXME: We currently ignore ProgressChange events from out-of-process
 // subframes both here and in BrowserParent. We may want to change this
 // behaviour in the future.
 if (!GetBrowsingContext()->IsTopContent()) {
   return NS_OK;
 }

 // NOTE: ProgressChange notifications delivered here are filtered by
 // nsBrowserStatusFilter, which passes meaningless values for all other
 // arguments, so they are ignored here.
 (void)SendOnProgressChange(aCurTotalProgress, aMaxTotalProgress);

 return NS_OK;
}

NS_IMETHODIMP BrowserChild::OnLocationChange(nsIWebProgress* aWebProgress,
                                            nsIRequest* aRequest,
                                            nsIURI* aLocation,
                                            uint32_t aFlags) {
 if (!IPCOpen() || mDestroyed || !mShouldSendWebProgressEventsToParent) {
   return NS_OK;
 }

 nsCOMPtr<nsIDocShell> docShell = do_QueryInterface(aWebProgress);
 if (!docShell) {
   MOZ_ASSERT_UNREACHABLE("aWebProgress is null or not a nsIDocShell?");
   return NS_ERROR_UNEXPECTED;
 }

 RefPtr<BrowsingContext> browsingContext = docShell->GetBrowsingContext();
 RefPtr<Document> document = browsingContext->GetExtantDocument();
 if (!document) {
   return NS_OK;
 }

 WebProgressData webProgressData;
 RequestData requestData;

 MOZ_TRY(PrepareProgressListenerData(aWebProgress, aRequest, webProgressData,
                                     requestData));

 Maybe<WebProgressLocationChangeData> locationChangeData;

 bool canGoBack = false;
 bool canGoBackIgnoringUserInteraction = false;
 bool canGoForward = false;
 if (!mozilla::SessionHistoryInParent()) {
   MOZ_TRY(WebNavigation()->GetCanGoBack(&canGoBack));
   MOZ_TRY(WebNavigation()->GetCanGoBackIgnoringUserInteraction(
       &canGoBackIgnoringUserInteraction));
   MOZ_TRY(WebNavigation()->GetCanGoForward(&canGoForward));
 }

 if (browsingContext->IsTopContent()) {
   MOZ_ASSERT(
       browsingContext == GetBrowsingContext(),
       "Toplevel content BrowsingContext which isn't GetBrowsingContext()?");

   locationChangeData.emplace();

   document->GetContentType(locationChangeData->contentType());
   locationChangeData->isNavigating() = docShell->GetIsNavigating();
   locationChangeData->documentURI() = document->GetDocumentURIObject();
   document->GetTitle(locationChangeData->title());
   document->GetCharacterSet(locationChangeData->charset());

   locationChangeData->mayEnableCharacterEncodingMenu() =
       docShell->GetMayEnableCharacterEncodingMenu();

   locationChangeData->contentPrincipal() = document->NodePrincipal();
   locationChangeData->contentPartitionedPrincipal() =
       document->PartitionedPrincipal();
   locationChangeData->policyContainer() = document->GetPolicyContainer();
   locationChangeData->referrerInfo() = document->ReferrerInfo();
   locationChangeData->isSyntheticDocument() = document->IsSyntheticDocument();

   if (nsCOMPtr<nsILoadGroup> loadGroup = document->GetDocumentLoadGroup()) {
     uint64_t requestContextID = 0;
     MOZ_TRY(loadGroup->GetRequestContextID(&requestContextID));
     locationChangeData->requestContextID() = Some(requestContextID);
   }

#ifdef MOZ_CRASHREPORTER
   if (CrashReporter::GetEnabled()) {
     nsCOMPtr<nsIURI> annotationURI;

     nsresult rv =
         NS_MutateURI(aLocation).SetUserPass(""_ns).Finalize(annotationURI);

     if (NS_FAILED(rv)) {
       // Ignore failures on about: URIs.
       annotationURI = aLocation;
     }

     CrashReporter::RecordAnnotationNSCString(
         CrashReporter::Annotation::URL, annotationURI->GetSpecOrDefault());
   }
#endif
 }

 (void)SendOnLocationChange(webProgressData, requestData, aLocation, aFlags,
                            canGoBack, canGoBackIgnoringUserInteraction,
                            canGoForward, locationChangeData);

 return NS_OK;
}

NS_IMETHODIMP BrowserChild::OnStatusChange(nsIWebProgress* aWebProgress,
                                          nsIRequest* aRequest,
                                          nsresult aStatus,
                                          const char16_t* aMessage) {
 if (!IPCOpen() || mDestroyed || !mShouldSendWebProgressEventsToParent) {
   return NS_OK;
 }

 // NOTE: StatusChange notifications delivered here are filtered by
 // nsBrowserStatusFilter, which passes meaningless values for all other
 // arguments, so they are ignored here.
 (void)SendOnStatusChange(nsDependentString(aMessage));

 return NS_OK;
}

NS_IMETHODIMP BrowserChild::OnSecurityChange(nsIWebProgress* aWebProgress,
                                            nsIRequest* aRequest,
                                            uint32_t aState) {
 // Security changes are now handled entirely in the parent process
 // so we don't need to worry about forwarding them (and we shouldn't
 // be receiving any to forward).
 return NS_OK;
}

NS_IMETHODIMP BrowserChild::OnContentBlockingEvent(nsIWebProgress* aWebProgress,
                                                  nsIRequest* aRequest,
                                                  uint32_t aEvent) {
 // The OnContentBlockingEvent only happenes in the parent process. It should
 // not be seen in the content process.
 MOZ_DIAGNOSTIC_ASSERT(
     false, "OnContentBlockingEvent should not be seen in content process.");
 return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP BrowserChild::NotifyNavigationFinished() {
 (void)SendNavigationFinished();
 return NS_OK;
}

nsresult BrowserChild::PrepareRequestData(nsIRequest* aRequest,
                                         RequestData& aRequestData) {
 nsCOMPtr<nsIChannel> channel = do_QueryInterface(aRequest);
 if (!channel) {
   aRequestData.requestURI() = nullptr;
   return NS_OK;
 }

 nsresult rv = channel->GetURI(getter_AddRefs(aRequestData.requestURI()));
 NS_ENSURE_SUCCESS(rv, rv);

 rv = channel->GetOriginalURI(
     getter_AddRefs(aRequestData.originalRequestURI()));
 NS_ENSURE_SUCCESS(rv, rv);

 rv = channel->GetCanceledReason(aRequestData.canceledReason());
 NS_ENSURE_SUCCESS(rv, rv);

 nsCOMPtr<nsIClassifiedChannel> classifiedChannel = do_QueryInterface(channel);
 if (classifiedChannel) {
   rv = classifiedChannel->GetMatchedList(aRequestData.matchedList());
   NS_ENSURE_SUCCESS(rv, rv);
 }
 return NS_OK;
}

nsresult BrowserChild::PrepareProgressListenerData(
   nsIWebProgress* aWebProgress, nsIRequest* aRequest,
   WebProgressData& aWebProgressData, RequestData& aRequestData) {
 nsCOMPtr<nsIDocShell> docShell = do_QueryInterface(aWebProgress);
 if (!docShell) {
   MOZ_ASSERT_UNREACHABLE("aWebProgress is null or not a nsIDocShell?");
   return NS_ERROR_UNEXPECTED;
 }

 aWebProgressData.browsingContext() = docShell->GetBrowsingContext();
 nsresult rv = aWebProgress->GetLoadType(&aWebProgressData.loadType());
 NS_ENSURE_SUCCESS(rv, rv);

 return PrepareRequestData(aRequest, aRequestData);
}

void BrowserChild::UpdateSessionStore() {
 if (mSessionStoreChild) {
   mSessionStoreChild->UpdateSessionStore();
 }
}

#ifdef XP_WIN
RefPtr<PBrowserChild::IsWindowSupportingProtectedMediaPromise>
BrowserChild::DoesWindowSupportProtectedMedia() {
 MOZ_ASSERT(
     NS_IsMainThread(),
     "Protected media support check should be done on main thread only.");
 if (mWindowSupportsProtectedMedia) {
   // If we've already checked and have a cached result, resolve with that.
   return IsWindowSupportingProtectedMediaPromise::CreateAndResolve(
       mWindowSupportsProtectedMedia.value(), __func__);
 }
 RefPtr<BrowserChild> self = this;
 // We chain off the promise rather than passing it directly so we can cache
 // the result and use that for future calls.
 return SendIsWindowSupportingProtectedMedia(ChromeOuterWindowID())
     ->Then(
         GetCurrentSerialEventTarget(), __func__,
         [self](bool isSupported) {
           // If a result was cached while this check was inflight, ensure the
           // results match.
           MOZ_ASSERT_IF(
               self->mWindowSupportsProtectedMedia,
               self->mWindowSupportsProtectedMedia.value() == isSupported);
           // Cache the response as it will not change during the lifetime
           // of this object.
           self->mWindowSupportsProtectedMedia = Some(isSupported);
           return IsWindowSupportingProtectedMediaPromise::CreateAndResolve(
               self->mWindowSupportsProtectedMedia.value(), __func__);
         },
         [](ResponseRejectReason reason) {
           return IsWindowSupportingProtectedMediaPromise::CreateAndReject(
               reason, __func__);
         });
}
#endif

void BrowserChild::NotifyContentBlockingEvent(
   uint32_t aEvent, nsIChannel* aChannel, bool aBlocked,
   const nsACString& aTrackingOrigin,
   const nsTArray<nsCString>& aTrackingFullHashes,
   const Maybe<
       mozilla::ContentBlockingNotifier::StorageAccessPermissionGrantedReason>&
       aReason,
   const Maybe<CanvasFingerprintingEvent>& aCanvasFingerprintingEvent) {
 if (!IPCOpen()) {
   return;
 }

 RequestData requestData;
 if (NS_SUCCEEDED(PrepareRequestData(aChannel, requestData))) {
   (void)SendNotifyContentBlockingEvent(
       aEvent, requestData, aBlocked, PromiseFlatCString(aTrackingOrigin),
       aTrackingFullHashes, aReason, aCanvasFingerprintingEvent);
 }
}

NS_IMETHODIMP
BrowserChild::ContentTransformsReceived(JSContext* aCx,
                                       dom::Promise** aPromise) {
 auto* globalObject = xpc::CurrentNativeGlobal(aCx);
 ErrorResult rv;
 if (mChildToParentConversionMatrix) {
   // Already received content transforms
   RefPtr<Promise> promise =
       Promise::CreateResolvedWithUndefined(globalObject, rv);
   promise.forget(aPromise);
   return rv.StealNSResult();
 }

 if (!mContentTransformPromise) {
   mContentTransformPromise = Promise::Create(globalObject, rv);
 }

 MOZ_ASSERT(globalObject == mContentTransformPromise->GetGlobalObject());
 NS_IF_ADDREF(*aPromise = mContentTransformPromise);
 return rv.StealNSResult();
}

already_AddRefed<nsIDragSession> BrowserChild::GetDragSession() {
 return RefPtr(mDragSession).forget();
}

void BrowserChild::SetDragSession(nsIDragSession* aSession) {
 mDragSession = aSession;
}

LazyLogModule gPointerRawUpdateEventListenersLog(
   "PointerRawUpdateEventListeners");

void BrowserChild::OnPointerRawUpdateEventListenerAdded(
   const nsPIDOMWindowInner* aWindow) {
 mPointerRawUpdateWindowCount++;
 MOZ_LOG(gPointerRawUpdateEventListenersLog, LogLevel::Info,
         ("Added for %p (total: %u)", aWindow, mPointerRawUpdateWindowCount));
}

void BrowserChild::OnPointerRawUpdateEventListenerRemoved(
   const nsPIDOMWindowInner* aWindow) {
 MOZ_ASSERT(mPointerRawUpdateWindowCount);
 if (MOZ_LIKELY(mPointerRawUpdateWindowCount)) {
   mPointerRawUpdateWindowCount--;
 }
 MOZ_LOG(gPointerRawUpdateEventListenersLog, LogLevel::Info,
         ("Removed for %p (remaining: %u)", aWindow,
          mPointerRawUpdateWindowCount));
}

BrowserChildMessageManager::BrowserChildMessageManager(
   BrowserChild* aBrowserChild)
   : ContentFrameMessageManager(new nsFrameMessageManager(aBrowserChild)),
     mBrowserChild(aBrowserChild) {}

BrowserChildMessageManager::~BrowserChildMessageManager() = default;

NS_IMPL_CYCLE_COLLECTION_CLASS(BrowserChildMessageManager)

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(BrowserChildMessageManager,
                                               DOMEventTargetHelper)
 NS_IMPL_CYCLE_COLLECTION_UNLINK(mMessageManager);
 NS_IMPL_CYCLE_COLLECTION_UNLINK(mBrowserChild);
 NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_REFERENCE
NS_IMPL_CYCLE_COLLECTION_UNLINK_END

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(BrowserChildMessageManager,
                                                 DOMEventTargetHelper)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mMessageManager)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mBrowserChild)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(BrowserChildMessageManager)
 NS_INTERFACE_MAP_ENTRY(nsIMessageSender)
 NS_INTERFACE_MAP_ENTRY_CONCRETE(ContentFrameMessageManager)
 NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)

NS_IMPL_ADDREF_INHERITED(BrowserChildMessageManager, DOMEventTargetHelper)
NS_IMPL_RELEASE_INHERITED(BrowserChildMessageManager, DOMEventTargetHelper)

JSObject* BrowserChildMessageManager::WrapObject(
   JSContext* aCx, JS::Handle<JSObject*> aGivenProto) {
 return ContentFrameMessageManager_Binding::Wrap(aCx, this, aGivenProto);
}

void BrowserChildMessageManager::MarkForCC() {
 if (mBrowserChild) {
   mBrowserChild->MarkScopesForCC();
 }
 EventListenerManager* elm = GetExistingListenerManager();
 if (elm) {
   elm->MarkForCC();
 }
 MessageManagerGlobal::MarkForCC();
}

Nullable<WindowProxyHolder> BrowserChildMessageManager::GetContent(
   ErrorResult& aError) {
 nsCOMPtr<nsIDocShell> docShell = GetDocShell(aError);
 if (!docShell) {
   return nullptr;
 }
 return WindowProxyHolder(docShell->GetBrowsingContext());
}

already_AddRefed<nsIDocShell> BrowserChildMessageManager::GetDocShell(
   ErrorResult& aError) {
 if (!mBrowserChild) {
   aError.Throw(NS_ERROR_NULL_POINTER);
   return nullptr;
 }
 nsCOMPtr<nsIDocShell> window =
     do_GetInterface(mBrowserChild->WebNavigation());
 return window.forget();
}

already_AddRefed<nsIEventTarget>
BrowserChildMessageManager::GetTabEventTarget() {
 return do_AddRef(GetMainThreadSerialEventTarget());
}

nsresult BrowserChildMessageManager::Dispatch(
   already_AddRefed<nsIRunnable>&& aRunnable) const {
 return SchedulerGroup::Dispatch(std::move(aRunnable));
}