CSSValue Immediates: Replace CSSValue usage with const references

Source/core/css/resolver/ElementStyleResources.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 19 matching lines @@
 #include "core/style/StylePendingImage.h"
 #include "platform/graphics/filters/FilterOperation.h"
 
 namespace blink {
 
 ElementStyleResources::ElementStyleResources()
     : m_deviceScaleFactor(1)
 {
 }
 
-PassRefPtr<StyleImage> ElementStyleResources::styleImage(Document& document, const TextLinkColors& textLinkColors, Color currentColor, CSSPropertyID property, CSSValue value)
+PassRefPtr<StyleImage> ElementStyleResources::styleImage(Document& document, const TextLinkColors& textLinkColors, Color currentColor, CSSPropertyID property, const CSSValue& value)
 {
     if (value.isImageValue())
         return cachedOrPendingFromValue(document, property, toCSSImageValue(value));
 
     if (value.isImageGeneratorValue())
         return generatedOrPendingFromValue(property, &toCSSImageGeneratorValue(value));
 
     if (value.isImageSetValue())
         return setOrPendingFromValue(property, toCSSImageSetValue(value));
 
@@ skipping 49 matching lines @@
 {
     m_pendingSVGDocuments.clear();
 }
 
 void ElementStyleResources::addPendingSVGDocument(FilterOperation* filterOperation, CSSSVGDocumentValue* cssSVGDocumentValue)
 {
     m_pendingSVGDocuments.set(filterOperation, cssSVGDocumentValue);
 }
 
 }