Bug 1154013 - When the vibrant region of a window changes, composite synchronously so that the window contents and the vibrancy update atomically. r=mattwoodrow

Differential Revision: https://phabricator.services.mozilla.com/D40556

--HG--
extra : moz-landing-system : lando

widget/cocoa/VibrancyManager.h

@@ -67,8 +67,9 @@ class VibrancyManager {
    * or remove existing ones as needed.
    * @param aType   The vibrancy type to use in the region.
    * @param aRegion The vibrant area, in device pixels.
+   * @return Whether the region changed.
    */
-  void UpdateVibrantRegion(VibrancyType aType, const LayoutDeviceIntRegion& aRegion);
+  bool UpdateVibrantRegion(VibrancyType aType, const LayoutDeviceIntRegion& aRegion);
 
   bool HasVibrantRegions() { return !mVibrantRegions.IsEmpty(); }
 

widget/cocoa/VibrancyManager.mm

@@ -12,14 +12,13 @@
 
 using namespace mozilla;
 
-void VibrancyManager::UpdateVibrantRegion(VibrancyType aType,
+bool VibrancyManager::UpdateVibrantRegion(VibrancyType aType,
                                           const LayoutDeviceIntRegion& aRegion) {
   if (aRegion.IsEmpty()) {
-    mVibrantRegions.Remove(uint32_t(aType));
-    return;
+    return mVibrantRegions.Remove(uint32_t(aType));
   }
   auto& vr = *mVibrantRegions.LookupOrAdd(uint32_t(aType));
-  vr.UpdateRegion(aRegion, mCoordinateConverter, mContainerView, ^() {
+  return vr.UpdateRegion(aRegion, mCoordinateConverter, mContainerView, ^() {
     return this->CreateEffectView(aType);
   });
 }

widget/cocoa/nsChildView.mm

@@ -2480,16 +2480,21 @@ void nsChildView::UpdateVibrancy(const nsTArray<ThemeGeometry>& aThemeGeometries
                             sourceListSelectionRegion, activeSourceListSelectionRegion);
 
   auto& vm = EnsureVibrancyManager();
-  vm.UpdateVibrantRegion(VibrancyType::LIGHT, vibrantLightRegion);
-  vm.UpdateVibrantRegion(VibrancyType::DARK, vibrantDarkRegion);
-  vm.UpdateVibrantRegion(VibrancyType::MENU, menuRegion);
-  vm.UpdateVibrantRegion(VibrancyType::TOOLTIP, tooltipRegion);
-  vm.UpdateVibrantRegion(VibrancyType::HIGHLIGHTED_MENUITEM, highlightedMenuItemRegion);
-  vm.UpdateVibrantRegion(VibrancyType::SHEET, sheetRegion);
-  vm.UpdateVibrantRegion(VibrancyType::SOURCE_LIST, sourceListRegion);
-  vm.UpdateVibrantRegion(VibrancyType::SOURCE_LIST_SELECTION, sourceListSelectionRegion);
-  vm.UpdateVibrantRegion(VibrancyType::ACTIVE_SOURCE_LIST_SELECTION,
-                         activeSourceListSelectionRegion);
+  bool changed = false;
+  changed |= vm.UpdateVibrantRegion(VibrancyType::LIGHT, vibrantLightRegion);
+  changed |= vm.UpdateVibrantRegion(VibrancyType::DARK, vibrantDarkRegion);
+  changed |= vm.UpdateVibrantRegion(VibrancyType::MENU, menuRegion);
+  changed |= vm.UpdateVibrantRegion(VibrancyType::TOOLTIP, tooltipRegion);
+  changed |= vm.UpdateVibrantRegion(VibrancyType::HIGHLIGHTED_MENUITEM, highlightedMenuItemRegion);
+  changed |= vm.UpdateVibrantRegion(VibrancyType::SHEET, sheetRegion);
+  changed |= vm.UpdateVibrantRegion(VibrancyType::SOURCE_LIST, sourceListRegion);
+  changed |= vm.UpdateVibrantRegion(VibrancyType::SOURCE_LIST_SELECTION, sourceListSelectionRegion);
+  changed |= vm.UpdateVibrantRegion(VibrancyType::ACTIVE_SOURCE_LIST_SELECTION,
+                                    activeSourceListSelectionRegion);
+
+  if (changed) {
+    SuspendAsyncCATransactions();
+  }
 }
 
 NSColor* nsChildView::VibrancyFillColorForThemeGeometryType(