tor-browser

commit 2f5c54b4543ddf1fac145ef6f704cd62af2109fa
parent 305f1022d1e65466b1cd97bcc0c5e69b5e556fc5
Author: Emilio Cobos Álvarez <emilio@crisal.io>
Date:   Tue,  4 Nov 2025 21:40:33 +0000

Bug 1998239 - Fix nsIFrame::GetNearestWidget to not use nsView::GetNearestWidget. r=jwatt

This unifies the popup and non-popup cases in preparation for
bug 1994942.

There's one tricky bit here, which is that we need to fix the
app-units-per-dev-px that we return the coordinates to.

nsView::GetNearestWidget returns the offset in its own coordinates, so
match that. That bug went unnoticed because we don't have zoomed
subdocuments inside popups.

Differential Revision: https://phabricator.services.mozilla.com/D271274

Diffstat:
M
layout/generic/nsIFrame.cpp
 | 
21
++++++++++-----------

1 file changed, 10 insertions(+), 11 deletions(-)
diff --git a/layout/generic/nsIFrame.cpp b/layout/generic/nsIFrame.cpp
@@ -7907,33 +7907,32 @@ nsIWidget* nsIFrame::GetNearestWidget() const {
 nsIWidget* nsIFrame::GetNearestWidget(nsPoint& aOffset) const {
   aOffset.MoveTo(0, 0);
   nsIFrame* frame = const_cast<nsIFrame*>(this);
+  const auto targetAPD = PresContext()->AppUnitsPerDevPixel();
+  auto curAPD = targetAPD;
   do {
     if (frame->IsMenuPopupFrame()) {
       return static_cast<nsMenuPopupFrame*>(frame)->GetWidget();
     }
     if (auto* view = frame->GetView()) {
-      // NOTE(emilio): NS_FRAME_IN_POPUP gets propagated across documents, so we
-      // just need to be careful to not jump to the view hierarchy in this case,
-      // since popups are not part of it.
-      if (!frame->HasAnyStateBits(NS_FRAME_IN_POPUP)) {
-        nsPoint offsetToWidget;
-        nsIWidget* widget = view->GetNearestWidget(&offsetToWidget);
-        aOffset += offsetToWidget;
+      if (auto* widget = view->GetWidget()) {
+        aOffset += view->ViewToWidgetOffset();
+        aOffset = aOffset.ScaleToOtherAppUnits(curAPD, targetAPD);
         return widget;
       }
-      MOZ_ASSERT(!view->GetWidget(),
-                 "Shouldn't have a nested widget inside a popup");
     }
     aOffset += frame->GetPosition();
     nsPoint crossDocOffset;
     frame =
         nsLayoutUtils::GetCrossDocParentFrameInProcess(frame, &crossDocOffset);
-    aOffset += crossDocOffset;
-    MOZ_ASSERT(frame, "Root frame should have a widget");
     if (!frame) {
       break;
     }
+    auto newAPD = frame->PresContext()->AppUnitsPerDevPixel();
+    aOffset = aOffset.ScaleToOtherAppUnits(curAPD, newAPD);
+    aOffset += crossDocOffset;
+    curAPD = newAPD;
   } while (true);
+  aOffset = aOffset.ScaleToOtherAppUnits(curAPD, targetAPD);
   return PresContext()->GetRootWidget();
 }