Optimize StylePropertySet::findPropertyIndex() to improve CSS properties performance

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 131 matching lines @@
 
 class ImmutableStylePropertySet : public StylePropertySet {
 public:
     ~ImmutableStylePropertySet();
     static PassRefPtr<ImmutableStylePropertySet> create(const CSSProperty* properties, unsigned count, CSSParserMode);
 
     unsigned propertyCount() const { return m_arraySize; }
 
     const CSSValue** valueArray() const;
     const StylePropertyMetadata* metadataArray() const;
+    int findPropertyIndex(CSSPropertyID) const;
 
     void* m_storage;
 
 private:
     ImmutableStylePropertySet(const CSSProperty*, unsigned count, CSSParserMode);
 };
 
 inline const CSSValue** ImmutableStylePropertySet::valueArray() const
 {
     return reinterpret_cast<const CSSValue**>(const_cast<const void**>(&(this->m_storage)));
@@ skipping 39 matching lines @@
     bool removePropertiesInSet(const CSSPropertyID* set, unsigned length);
     void removeEquivalentProperties(const StylePropertySet*);
     void removeEquivalentProperties(const CSSStyleDeclaration*);
 
     void mergeAndOverrideOnConflict(const StylePropertySet*);
 
     void clear();
     void parseDeclaration(const String& styleDeclaration, StyleSheetContents* contextStyleSheet);
 
     CSSStyleDeclaration* ensureCSSStyleDeclaration();
+    int findPropertyIndex(CSSPropertyID) const;
 
     Vector<CSSProperty, 4> m_propertyVector;
 
 private:
     explicit MutableStylePropertySet(CSSParserMode);
     explicit MutableStylePropertySet(const StylePropertySet&);
     MutableStylePropertySet(const CSSProperty* properties, unsigned count);
 
     bool removeShorthandProperty(CSSPropertyID);
     CSSProperty* findCSSPropertyWithID(CSSPropertyID);
@@ skipping 39 matching lines @@
 {
     if (!derefBase())
         return;
 
     if (m_isMutable)
         delete toMutableStylePropertySet(this);
     else
         delete toImmutableStylePropertySet(this);
 }
 
+inline int StylePropertySet::findPropertyIndex(CSSPropertyID propertyID) const
+{
+    if (m_isMutable)
+        return toMutableStylePropertySet(this)->findPropertyIndex(propertyID);
+    return toImmutableStylePropertySet(this)->findPropertyIndex(propertyID);
+}
+
 } // namespace WebCore
 
 #endif // StylePropertySet_h