Add WebScopedAXContext to allow a one-time snapshot of accessibility.

public/web/WebAXObject.h

 /*
  * Copyright (C) 2009 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 25 matching lines @@
 #include "../platform/WebVector.h"
 #include "WebAXEnums.h"
 
 #if BLINK_IMPLEMENTATION
 namespace WTF { template <typename T> class PassRefPtr; }
 #endif
 
 namespace blink {
 
 class AXObject;
+class ScopedAXObjectCache;
+class WebAXObject;
 class WebNode;
 class WebDocument;
 class WebString;
 class WebURL;
 struct WebPoint;
 struct WebRect;
 
+// An instance of this class, while kept alive, indicates that accessibility
+// should be temporarily enabled. If accessibility was enabled globally
+// (WebSettings::setAccessibilityEnabled), this will have no effect.
+class WebScopedAXContext {
+public:
+    BLINK_EXPORT WebScopedAXContext(WebDocument& rootDocument);
+    BLINK_EXPORT ~WebScopedAXContext();
+
+    BLINK_EXPORT WebAXObject root() const;
+
+private:
+    WebPrivatePtr<ScopedAXObjectCache> m_private;
+};
+
 // A container for passing around a reference to AXObject.
 class WebAXObject {
 public:
     ~WebAXObject() { reset(); }
 
     WebAXObject() { }
     WebAXObject(const WebAXObject& o) { assign(o); }
     WebAXObject& operator=(const WebAXObject& o)
     {
         assign(o);
@@ skipping 201 matching lines @@
     operator WTF::PassRefPtr<AXObject>() const;
 #endif
 
 private:
     WebPrivatePtr<AXObject> m_private;
 };
 
 } // namespace blink
 
 #endif