Repaint squashing content in cases where the entire frame is repainting.

Source/core/rendering/compositing/RenderLayerCompositor.cpp

 /*
  * Copyright (C) 2009, 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 662 matching lines @@
 }
 
 void RenderLayerCompositor::repaintCompositedLayers()
 {
     recursiveRepaintLayer(rootRenderLayer());
 }
 
 void RenderLayerCompositor::recursiveRepaintLayer(RenderLayer* layer)
 {
     // FIXME: This method does not work correctly with transforms.
-    if (layer->compositingState() == PaintsIntoOwnBacking)
-        layer->repainter().setBackingNeedsRepaint();
+    if (layer->compositingState() == PaintsIntoOwnBacking) {
+        layer->compositedLayerMapping()->setContentsNeedDisplay();
+        // This function is called only when it is desired to repaint the entire compositing graphics layer tree.
+        // This includes squashing.
+        layer->compositedLayerMapping()->setSquashingContentsNeedDisplay();
+    }
 
     layer->stackingNode()->updateLayerListsIfNeeded();
 
 #if ASSERT_ENABLED
     LayerListMutationDetector mutationChecker(layer->stackingNode());
 #endif
 
     unsigned childrenToVisit = NormalFlowChildren;
     if (layer->hasCompositingDescendant())
         childrenToVisit |= PositiveZOrderChildren | NegativeZOrderChildren;
@@ skipping 551 matching lines @@
     } else if (graphicsLayer == m_scrollLayer.get()) {
         name = "LocalFrame Scrolling Layer";
     } else {
         ASSERT_NOT_REACHED();
     }
 
     return name;
 }
 
 } // namespace WebCore