Don't schedule an animation during compositing dirty-bit setting unless needed.

Source/core/frame/FrameView.cpp

Index: Source/core/frame/FrameView.cpp
diff --git a/Source/core/frame/FrameView.cpp b/Source/core/frame/FrameView.cpp
index bb0492541323368e4641aef3a4acc42f7ba7b61b..09c851b53ac02caece93d85a83ada1998d07e330 100644
--- a/Source/core/frame/FrameView.cpp
+++ b/Source/core/frame/FrameView.cpp
@@ -2784,8 +2784,14 @@ void FrameView::updateLayoutAndStyleForPainting()
     RefPtr<FrameView> protector(this);
 
     updateLayoutAndStyleIfNeededRecursive();
-    if (RenderView* view = renderView())
+    if (RenderView* view = renderView()) {
+        ASSERT(!view->needsLayout());
         view->compositor()->updateCompositingLayers();
+
+        // FIXME: we should not have any dirty bits left at this point. Unfortunately, this is not yet the case because
+        // the code in updateCompositingLayers sometimes creates new dirty bits when updating direct compositing reasons.
+        view->compositor()->scheduleAnimationIfNeeded();
+    }
 }
 
 void FrameView::updateLayoutAndStyleIfNeededRecursive()