Change PaintLayer::m_layoutObject to a reference.

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

 /*
  * Copyright (C) 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2014 Google 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
@@ skipping 39 matching lines @@
       m_compositingAncestor = &layer;
       if (layer.stackingNode()->isStackingContext())
         m_compositingStackingContext = &layer;
     }
   }
 
   const PaintLayer* compositingContainer(const PaintLayer& layer) const {
     if (layer.stackingNode()->isStacked())
       return m_compositingStackingContext;
 
-    if (layer.layoutObject()->isFloatingWithNonContainingBlockParent())
+    if (layer.layoutObject().isFloatingWithNonContainingBlockParent())
       return layer.enclosingLayerWithCompositedLayerMapping(ExcludeSelf);
 
     return m_compositingAncestor;
   }
 
   const PaintLayer* compositingStackingContext() const {
     return m_compositingStackingContext;
   }
 
  private:
@@ skipping 57 matching lines @@
         ->assertNeedsToUpdateGraphicsLayerBitsCleared();
 
   for (PaintLayer* child = layer.firstChild(); child;
        child = child->nextSibling())
     assertNeedsToUpdateGraphicsLayerBitsCleared(*child);
 }
 
 #endif
 
 }  // namespace blink