Move CSSOM classes to using MutableStylePropertySet over StylePropertySet.

Source/core/css/StylePropertySet.h

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2008, 2012 Apple 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.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 129 matching lines @@
     PassRefPtr<StylePropertySet> immutableCopyIfNeeded() const;
 
     void removeEquivalentProperties(const StylePropertySet*);
     void removeEquivalentProperties(const CSSStyleDeclaration*);
 
     PassRefPtr<MutableStylePropertySet> copyPropertiesInSet(const Vector<CSSPropertyID>&) const;
     
     String asText() const;
 
     PropertySetCSSStyleDeclaration* cssStyleDeclaration();
-    CSSStyleDeclaration* ensureCSSStyleDeclaration();
-    CSSStyleDeclaration* ensureInlineCSSStyleDeclaration(const StyledElement* parentElement);
 
     bool isMutable() const { return m_isMutable; }
     bool hasCSSOMWrapper() const { return m_ownsCSSOMWrapper; }
 
     bool hasFailedOrCanceledSubresources() const;
 
     static unsigned averageSizeInBytes();
     void reportMemoryUsage(MemoryObjectInfo*) const;
 
 #ifndef NDEBUG
@@ skipping 59 matching lines @@
     return reinterpret_cast<const StylePropertyMetadata*>(&reinterpret_cast<const char*>((&static_cast<const ImmutableStylePropertySet*>(this)->m_storage))[m_arraySize * sizeof(CSSValue*)]);
 }
 
 class MutableStylePropertySet : public StylePropertySet {
 public:
     static PassRefPtr<MutableStylePropertySet> create(CSSParserMode = CSSQuirksMode);
     static PassRefPtr<MutableStylePropertySet> create(const CSSProperty* properties, unsigned count);
 
     MutableStylePropertySet(const StylePropertySet&);
 
+    CSSStyleDeclaration* ensureCSSStyleDeclaration();
+    CSSStyleDeclaration* ensureInlineCSSStyleDeclaration(const StyledElement* parentElement);
+
     Vector<CSSProperty, 4> m_propertyVector;
 
 private:
     MutableStylePropertySet(CSSParserMode cssParserMode)
         : StylePropertySet(cssParserMode)
     { }
     MutableStylePropertySet(const CSSProperty* properties, unsigned count);
 };
 
 inline Vector<CSSProperty, 4>& StylePropertySet::mutablePropertyVector()
@@ skipping 27 matching lines @@
 
     if (m_isMutable)
         delete static_cast<MutableStylePropertySet*>(this);
     else
         delete static_cast<ImmutableStylePropertySet*>(this);
 }
 
 } // namespace WebCore
 
 #endif // StylePropertySet_h