Bug 1772432 - Remove nsWidgetInitData::mMouseTransparent. r=stransky

Instead, have the menu popup frame call SetWindowMouseTransparent (since
it needs to anyways to deal with dynamic changes).

Differential Revision: https://phabricator.services.mozilla.com/D148211

layout/xul/nsMenuPopupFrame.cpp

@@ -333,8 +333,6 @@ nsresult nsMenuPopupFrame::CreateWidgetForView(nsView* aView) {
                                            nsGkAtoms::drag, eIgnoreCase)) {
       widgetData.mIsDragPopup = true;
     }
-
-    widgetData.mMouseTransparent = IsMouseTransparent();
   }
 
   nsAutoString title;
@@ -395,6 +393,7 @@ nsresult nsMenuPopupFrame::CreateWidgetForView(nsView* aView) {
 
   nsIWidget* widget = aView->GetWidget();
   widget->SetTransparencyMode(mode);
+  widget->SetWindowMouseTransparent(IsMouseTransparent());
   widget->SetWindowShadowStyle(GetShadowStyle());
   widget->SetWindowOpacity(StyleUIReset()->mWindowOpacity);
   widget->SetWindowTransform(ComputeWidgetTransform());

widget/cocoa/nsCocoaWindow.mm

@@ -348,7 +348,6 @@ nsresult nsCocoaWindow::Create(nsIWidget* aParent, nsNativeWidget aNativeParent,
   NS_ENSURE_SUCCESS(rv, rv);
 
   if (mWindowType == eWindowType_popup) {
-    SetWindowMouseTransparent(aInitData->mMouseTransparent);
     // now we can convert widgetRect to device pixels for the window we created,
     // as the child view expects a rect expressed in the dev pix of its parent
     LayoutDeviceIntRect devRect = RoundedToInt(newBounds * GetDesktopToDeviceScale());

widget/gtk/nsWindow.cpp

@@ -5511,7 +5511,6 @@ nsresult nsWindow::Create(nsIWidget* aParent, nsNativeWidget aNativeParent,
   // and can be changed so we use WaylandPopupIsPermanent() to get
   // recent popup config (Bug 1728952).
   mNoAutoHide = aInitData && aInitData->mNoAutoHide;
-  mMouseTransparent = aInitData && aInitData->mMouseTransparent;
 
   // Popups that are not noautohide are only temporary. The are used
   // for menus and the like and disappear when another window is used.

widget/nsWidgetInitData.h

@@ -105,9 +105,6 @@ struct nsWidgetInitData {
   bool mIsAnimationSuppressed = false;
   // true if the window should support an alpha channel, if available.
   bool mSupportTranslucency = false;
-  // true if the window should be transparent to mouse events. Currently this is
-  // only valid for eWindowType_popup widgets
-  bool mMouseTransparent = false;
   bool mHasRemoteContent = false;
   bool mAlwaysOnTop = false;
   // Is PictureInPicture window

widget/windows/nsWindow.cpp

@@ -971,12 +971,6 @@ nsresult nsWindow::Create(nsIWidget* aParent, nsNativeWidget aNativeParent,
         ShouldUseOffMainThreadCompositing()) {
       extendedStyle |= WS_EX_COMPOSITED;
     }
-
-    if (aInitData->mMouseTransparent) {
-      // This flag makes the window transparent to mouse events
-      mMouseTransparent = true;
-      extendedStyle |= WS_EX_TRANSPARENT;
-    }
   } else if (mWindowType == eWindowType_invisible) {
     // Make sure CreateWindowEx succeeds at creating a toplevel window
     style &= ~0x40000000;  // WS_CHILDWINDOW