Add a FOUC painting test.

Source/core/layout/compositing/CompositedDeprecatedPaintLayerMapping.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 2007 matching lines @@
     // FIXME: need to split out paint invalidations for the background.
     ApplyToGraphicsLayers(this, SetContentsNeedsDisplayFunctor(), ApplyToContentLayers);
 }
 
 struct SetContentsNeedsDisplayInRectFunctor {
     void operator() (GraphicsLayer* layer) const
     {
         if (layer->drawsContent()) {
             IntRect layerDirtyRect = r;
             layerDirtyRect.move(-layer->offsetFromLayoutObject());
+            // fprintf(stderr, "SetContentsNeedsDisplayInRectFunctor\n");

[dglazkov, 2015/09/08 17:54:05]

Remove maybe?

             layer->setNeedsDisplayInRect(layerDirtyRect, invalidationReason);
         }
     }
 
     IntRect r;
     PaintInvalidationReason invalidationReason;
 };
 
 // r is in the coordinate space of the layer's layout object
 void CompositedDeprecatedPaintLayerMapping::setContentsNeedDisplayInRect(const LayoutRect& r, PaintInvalidationReason invalidationReason)
@@ skipping 359 matching lines @@
     } else if (graphicsLayer == m_scrollingBlockSelectionLayer.get()) {
         name = "Scrolling Block Selection Layer";
     } else {
         ASSERT_NOT_REACHED();
     }
 
     return name;
 }
 
 } // namespace blink