Remove the CompositedLayerMappingPtr smart ptr.

Source/core/rendering/compositing/GraphicsLayerTreeBuilder.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 46 matching lines @@
 
 void GraphicsLayerTreeBuilder::rebuild(RenderLayer& layer, AncestorInfo info)
 {
     // Make the layer compositing if necessary, and set up clipping and content layers.
     // Note that we can only do work here that is independent of whether the descendant layers
     // have been processed. computeCompositingRequirements() will already have done the repaint if necessary.
 
     layer.stackingNode()->updateLayerListsIfNeeded();
 
     const bool hasCompositedLayerMapping = layer.hasCompositedLayerMapping();
-    CompositedLayerMappingPtr currentCompositedLayerMapping = layer.compositedLayerMapping();
+    CompositedLayerMapping* currentCompositedLayerMapping = layer.compositedLayerMapping();
 
     // If this layer has a compositedLayerMapping, then that is where we place subsequent children GraphicsLayers.
     // Otherwise children continue to append to the child list of the enclosing layer.
     GraphicsLayerVector layerChildren;
     AncestorInfo infoForChildren(info);
     if (hasCompositedLayerMapping) {
         infoForChildren.childLayersOfEnclosingCompositedLayer = &layerChildren;
         infoForChildren.enclosingCompositedLayer = &layer;
     }
 
@@ skipping 48 matching lines @@
     }
 
     if (layer.scrollParent()
         && layer.scrollParent()->hasCompositedLayerMapping()
         && layer.scrollParent()->compositedLayerMapping()->needsToReparentOverflowControls()
         && layer.scrollParent()->scrollableArea()->topmostScrollChild() == &layer)
         info.childLayersOfEnclosingCompositedLayer->append(layer.scrollParent()->compositedLayerMapping()->detachLayerForOverflowControls(*info.enclosingCompositedLayer));
 }
 
 }