Make Blink stop scheduling its own Layout, and use the compositor's timer instead

Source/core/rendering/RenderIFrame.cpp

 /*
  * Copyright (C) 2010 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 97 matching lines @@
     // both padding and border to the child's logical height here.
     FrameView* childFrameView = toFrameView(widget());
     if (childFrameView) // Widget should never be null during layout(), but just in case.
         setLogicalHeight(childFrameView->contentsHeight() + borderTop() + borderBottom() + paddingTop() + paddingBottom());
     updateLogicalHeight();
 
     updateWidgetPosition(); // Notify the Widget of our final height.
 
     // Assert that the child document did a complete layout.
     RenderView* childRoot = childFrameView ? childFrameView->frame()->contentRenderer() : 0;
-    ASSERT(!childFrameView || !childFrameView->layoutPending());
+    ASSERT(!childFrameView || !childFrameView->layoutIsScheduledWithEmbedder());
     ASSERT_UNUSED(childRoot, !childRoot || !childRoot->needsLayout());
 }
 
 void RenderIFrame::layout()
 {
     StackStats::LayoutCheckPoint layoutCheckPoint;
     ASSERT(needsLayout());
 
     if (isSeamless()) {
         layoutSeamlessly();
         // Do not return so as to share the layer and overflow updates below.
     } else {
         updateLogicalWidth();
         // No kids to layout as a replaced element.
         updateLogicalHeight();
     }
 
     m_overflow.clear();
     addVisualEffectOverflow();
     updateLayerTransform();
 
     setNeedsLayout(false);
 }
 
 }