Don't try to paint graphics layers inside throttled frames

third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp

 /*
  * Copyright (C) 2009, 2010, 2011 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 2126 matching lines @@
 
     if (!(paintLayerFlags & PaintLayerPaintingOverflowContents)) {
         LayoutRect bounds = paintInfo.compositedBounds;
         bounds.move(paintInfo.paintLayer->subpixelAccumulation());
         dirtyRect.intersect(pixelSnappedIntRect(bounds));
     } else {
         dirtyRect.move(roundedIntSize(paintInfo.paintLayer->subpixelAccumulation()));
     }
 
 #if ENABLE(ASSERT)
-    paintInfo.paintLayer->layoutObject()->assertSubtreeIsLaidOut();
+    if (!layoutObject()->view()->frame() || !layoutObject()->view()->frame()->shouldThrottleRendering())
+        paintInfo.paintLayer->layoutObject()->assertSubtreeIsLaidOut();
 #endif
 
     float deviceScaleFactor = blink::deviceScaleFactor(paintInfo.paintLayer->layoutObject()->frame());
     context.setDeviceScaleFactor(deviceScaleFactor);
 
     if (paintInfo.paintLayer->compositingState() != PaintsIntoGroupedBacking) {
         // FIXME: GraphicsLayers need a way to split for multicol.
         PaintLayerPaintingInfo paintingInfo(paintInfo.paintLayer, LayoutRect(dirtyRect), GlobalPaintNormalPhase, paintInfo.paintLayer->subpixelAccumulation());
         PaintLayerPainter(*paintInfo.paintLayer).paintLayerContents(context, paintingInfo, paintLayerFlags);
 
@@ skipping 414 matching lines @@
     } else if (graphicsLayer == m_scrollingContentsLayer.get()) {
         name = "Scrolling Contents Layer";
     } else {
         ASSERT_NOT_REACHED();
     }
 
     return name;
 }
 
 } // namespace blink