Add flag for tracking descendant paint property updates

third_party/WebKit/Source/core/frame/FrameView.cpp

Index: third_party/WebKit/Source/core/frame/FrameView.cpp
diff --git a/third_party/WebKit/Source/core/frame/FrameView.cpp b/third_party/WebKit/Source/core/frame/FrameView.cpp
index 1e1bf54b71d6690470c8e3bd803e423ea33ab088..daa201599aa31f263a7fd7e28793e60cdf33439d 100644
--- a/third_party/WebKit/Source/core/frame/FrameView.cpp
+++ b/third_party/WebKit/Source/core/frame/FrameView.cpp
@@ -1483,7 +1483,7 @@ void FrameView::addBackgroundAttachmentFixedObject(LayoutObject* object) {
   if (RuntimeEnabledFeatures::slimmingPaintV2Enabled()) {
     setNeedsPaintPropertyUpdate();
     // The object's scroll properties are not affected by its own background.
-    object->setAllAncestorsNeedPaintPropertyUpdate();
+    object->setAncestorsNeedPaintPropertyUpdateForMainThreadScrolling();
   }
 }
 
@@ -1499,7 +1499,7 @@ void FrameView::removeBackgroundAttachmentFixedObject(LayoutObject* object) {
   if (RuntimeEnabledFeatures::slimmingPaintV2Enabled()) {
     setNeedsPaintPropertyUpdate();
     // The object's scroll properties are not affected by its own background.
-    object->setAllAncestorsNeedPaintPropertyUpdate();
+    object->setAncestorsNeedPaintPropertyUpdateForMainThreadScrolling();
   }
 }