CSSValue Immediates: Change CSSValue to an object instead of a pointer

Source/core/style/StyleFetchedImageSet.cpp

 /*
  * Copyright (C) 2012 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 29 matching lines @@
     m_isImageResourceSet = true;
     m_bestFitImage->addClient(this);
 }
 
 
 StyleFetchedImageSet::~StyleFetchedImageSet()
 {
     m_bestFitImage->removeClient(this);
 }
 
-PassRefPtrWillBeRawPtr<CSSValue> StyleFetchedImageSet::cssValue() const
+NullableCSSValue StyleFetchedImageSet::cssValue() const
 {
     return m_imageSetValue;
 }
 
 bool StyleFetchedImageSet::canRender(const LayoutObject& layoutObject, float multiplier) const
 {
     return m_bestFitImage->canRender(layoutObject, multiplier);
 }
 
 bool StyleFetchedImageSet::isLoaded() const
@@ skipping 52 matching lines @@
 {
     return m_bestFitImage->imageForLayoutObject(layoutObject);
 }
 
 bool StyleFetchedImageSet::knownToBeOpaque(const LayoutObject* layoutObject) const
 {
     return m_bestFitImage->currentFrameKnownToBeOpaque(layoutObject);
 }
 
 } // namespace blink