Implement computedRole and computedName (behind a flag)

Source/core/dom/AXObjectCache.h

 /*
  * Copyright (C) 2003, 2006, 2007, 2008, 2009, 2010, 2011 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 102 matching lines @@
 
     // Called when the scroll offset changes.
     virtual void handleScrollPositionChanged(FrameView*) = 0;
     virtual void handleScrollPositionChanged(RenderObject*) = 0;
 
     // Called when scroll bars are added / removed (as the view resizes).
     virtual void handleScrollbarUpdate(FrameView*) = 0;
     virtual void handleLayoutComplete(RenderObject*) = 0;
     virtual void handleScrolledToAnchor(const Node* anchorNode) = 0;
 
+    virtual const AtomicString& computedRoleForNode(Node*) = 0;
+    virtual String computedNameForNode(Node*) = 0;
+
 protected:
     AXObjectCache();
 };
 
+class ScopedAXObjectCache {
+    WTF_MAKE_NONCOPYABLE(ScopedAXObjectCache);
+public:
+    explicit ScopedAXObjectCache(Document&);
+    ~ScopedAXObjectCache();
+
+    AXObjectCache* get();
+    AXObjectCache* operator->();
+
+private:
+    Document& m_document;
+    AXObjectCache* m_cache;
+    bool m_isScoped;
+};
+
 }
 
 #endif