Support invalidation sets for :host pseudo.

Source/core/css/RuleFeature.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 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 120 matching lines @@
         UseSubtreeStyleChange
     };
 
     static InvalidationSetMode supportsClassDescendantInvalidation(const CSSSelector&);
 
     void collectFeaturesFromSelector(const CSSSelector&, FeatureMetadata&, InvalidationSetMode);
     void collectFeaturesFromSelectorList(const CSSSelectorList*, FeatureMetadata&, InvalidationSetMode);
 
     DescendantInvalidationSet& ensureClassInvalidationSet(const AtomicString& className);
     InvalidationSetMode updateClassInvalidationSets(const CSSSelector&);
+    const CSSSelector* extractInvalidationSetFeatures(const CSSSelector&, Vector<AtomicString>& classes, AtomicString& id, AtomicString& tagName);
+    void addFeaturesToInvalidationSets(const CSSSelector&, const Vector<AtomicString>& classes, AtomicString id, AtomicString tagName);
 
     void addClassToInvalidationSet(const AtomicString& className, Element*);
 
     InvalidationList& ensurePendingInvalidationList(Element*);
 
     FeatureMetadata m_metadata;
     InvalidationSetMap m_classInvalidationSets;
     PendingInvalidationMap m_pendingInvalidationMap;
 
     bool m_targetedStyleRecalcEnabled;
 };
 
 
 } // namespace WebCore
 
 #endif // RuleFeature_h