CSSValue Immediates: Replace CSSValue usage with const references

Source/core/css/CSSCrossfadeValue.cpp

 /*
  * Copyright (C) 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 16 matching lines @@
 #include "core/css/CSSCrossfadeValue.h"
 
 #include "core/css/CSSImageValue.h"
 #include "core/layout/LayoutObject.h"
 #include "core/style/StyleFetchedImage.h"
 #include "platform/graphics/CrossfadeGeneratedImage.h"
 #include "wtf/text/StringBuilder.h"
 
 namespace blink {
 
-static bool subimageIsPending(CSSValue value)
+static bool subimageIsPending(const CSSValue& value)
 {
     if (value.isImageValue())
         return toCSSImageValue(value).cachedOrPendingImage()->isPendingImage();
 
     if (value.isImageGeneratorValue())
         return toCSSImageGeneratorValue(value).isPending();
 
     ASSERT_NOT_REACHED();
 
     return false;
 }
 
-static bool subimageKnownToBeOpaque(CSSValue value, const LayoutObject* layoutObject)
+static bool subimageKnownToBeOpaque(const CSSValue& value, const LayoutObject* layoutObject)
 {
     if (value.isImageValue())
         return toCSSImageValue(value).knownToBeOpaque(layoutObject);
 
     if (value.isImageGeneratorValue())
         return toCSSImageGeneratorValue(value).knownToBeOpaque(layoutObject);
 
     ASSERT_NOT_REACHED();
 
     return false;
 }
 
-static ImageResource* cachedImageForCSSValue(CSSValue value, Document* document)
+static ImageResource* cachedImageForCSSValue(const CSSValue& value, Document* document)
 {
     if (value.isImageValue()) {
         StyleFetchedImage* styleImageResource = toCSSImageValue(value).cachedImage(document);
         if (!styleImageResource)
             return 0;
 
         return styleImageResource->cachedImage();
     }
 
     if (value.isImageGeneratorValue()) {
@@ skipping 142 matching lines @@
 
 DEFINE_TRACE_AFTER_DISPATCH(CSSCrossfadeValue)
 {
     visitor->trace(m_fromValue);
     visitor->trace(m_toValue);
     visitor->trace(m_percentageValue);
     CSSImageGeneratorValue::traceAfterDispatch(visitor);
 }
 
 } // namespace blink