Remove the CompositedLayerMappingPtr smart ptr.

Source/core/rendering/RenderLayer.cpp

Index: Source/core/rendering/RenderLayer.cpp
diff --git a/Source/core/rendering/RenderLayer.cpp b/Source/core/rendering/RenderLayer.cpp
index 5c56e8d6d384f25e1139010151036111c854483c..c18e58eea7b546a20e12651222f5ce5e5e31b0cd 100644
--- a/Source/core/rendering/RenderLayer.cpp
+++ b/Source/core/rendering/RenderLayer.cpp
@@ -3305,7 +3305,7 @@ bool RenderLayer::isAllowedToQueryCompositingState() const
     return renderer()->document().lifecycle().state() >= DocumentLifecycle::InCompositingUpdate;
 }
 
-CompositedLayerMappingPtr RenderLayer::compositedLayerMapping() const
+CompositedLayerMapping* RenderLayer::compositedLayerMapping() const
 {
     ASSERT(isAllowedToQueryCompositingState());
     return m_compositedLayerMapping.get();
@@ -3335,7 +3335,7 @@ GraphicsLayer* RenderLayer::graphicsLayerBackingForScrolling() const
     }
 }
 
-CompositedLayerMappingPtr RenderLayer::ensureCompositedLayerMapping()
+CompositedLayerMapping* RenderLayer::ensureCompositedLayerMapping()
 {
     if (!m_compositedLayerMapping) {
         m_compositedLayerMapping = adoptPtr(new CompositedLayerMapping(*this));