Invalidate only non-scrolling layers for non-scrolling content.

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

 /*
  * 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 110 matching lines @@
     bool hasChildTransformLayer() const { return m_childTransformLayer.get(); }
     GraphicsLayer* childTransformLayer() const { return m_childTransformLayer.get(); }
 
     GraphicsLayer* squashingContainmentLayer() const { return m_squashingContainmentLayer.get(); }
     GraphicsLayer* squashingLayer() const { return m_squashingLayer.get(); }
 
     void setSquashingContentsNeedDisplay();
     void setContentsNeedDisplay();
     // LayoutRect is in the coordinate space of the layer's layout object.
     void setContentsNeedDisplayInRect(const LayoutRect&, PaintInvalidationReason, const DisplayItemClient&);
+    // Invalidates just the non-scrolling content layers.
+    void setNonScrollingContentsNeedDisplayInRect(const LayoutRect&, PaintInvalidationReason, const DisplayItemClient&);
     // Invalidates just scrolling content layers.
     void setScrollingContentsNeedDisplayInRect(const LayoutRect&, PaintInvalidationReason, const DisplayItemClient&);
 
     // This is called only if we are tracking paint invalidation for testing, or ENABLE(ASSERT)
     // for error checking and debugging.
     void displayItemClientWasInvalidated(const DisplayItemClient&, PaintInvalidationReason);
     // Invalidates just scrolling content layers.
     void scrollingDisplayItemClientWasInvalidated(const DisplayItemClient&, PaintInvalidationReason);
 
     // Notification from the layoutObject that its content changed.
@@ skipping 317 matching lines @@
 
     unsigned m_backgroundLayerPaintsFixedRootBackground : 1;
     unsigned m_scrollingContentsAreEmpty : 1;
 
     friend class CompositedLayerMappingTest;
 };
 
 } // namespace blink
 
 #endif // CompositedLayerMapping_h