Add support for element ids in TargetedStyleRecalc

Source/core/css/invalidation/DescendantInvalidationSet.h

 /*
  * Copyright (C) 2014 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 46 matching lines @@
     void addId(const AtomicString& id);
     void addTagName(const AtomicString& tagName);
     void addAttribute(const AtomicString& attributeLocalName);
 
     // Appends the classes in this DescendantInvalidationSet to the vector.
     void getClasses(Vector<AtomicString>& classes) const;
 
     // Appends the attributes in this DescendantInvalidationSet to the vector.
     void getAttributes(Vector<AtomicString>& attributes) const;
 
+    // Appends the ids in this DescendantInvalidationSet to the vector.
+    void getIds(Vector<AtomicString>& ids) const;
+
     void setWholeSubtreeInvalid();
     bool wholeSubtreeInvalid() const { return m_allDescendantsMightBeInvalid; }
 private:
     DescendantInvalidationSet();
 
     HashSet<AtomicString>& ensureClassSet();
     HashSet<AtomicString>& ensureIdSet();
     HashSet<AtomicString>& ensureTagNameSet();
     HashSet<AtomicString>& ensureAttributeSet();
 
     // If true, all descendants might be invalidated, so a full subtree recalc is required.
     bool m_allDescendantsMightBeInvalid;
 
     // FIXME: optimize this if it becomes a memory issue.
     OwnPtr<HashSet<AtomicString> > m_classes;
     OwnPtr<HashSet<AtomicString> > m_ids;
     OwnPtr<HashSet<AtomicString> > m_tagNames;
     OwnPtr<HashSet<AtomicString> > m_attributes;
 };
 
 } // namespace WebCore
 
 #endif // DescendantInvalidationSet_h