binding: Makes XxxObserverCallback use V8PrivateProperty instead of V8HiddenValue.

third_party/WebKit/Source/bindings/core/v8/V8MutationCallback.h

 /*
  * Copyright (C) 2013 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:
  * 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 10 matching lines @@
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef V8MutationCallback_h
 #define V8MutationCallback_h
 
 #include "bindings/core/v8/ActiveDOMCallback.h"
 #include "bindings/core/v8/ScopedPersistent.h"
-#include "bindings/core/v8/ScriptState.h"
 #include "core/dom/MutationCallback.h"
-#include "wtf/OwnPtr.h"
 #include "wtf/RefPtr.h"
 #include <v8.h>
 
 namespace blink {
 
 class ExecutionContext;
+class ScriptState;
 
 class V8MutationCallback final : public MutationCallback, public ActiveDOMCallback {
     USING_GARBAGE_COLLECTED_MIXIN(V8MutationCallback);
 public:
     static V8MutationCallback* create(v8::Local<v8::Function> callback, v8::Local<v8::Object> owner, ScriptState* scriptState)
     {
         return new V8MutationCallback(callback, owner, scriptState);
     }
     ~V8MutationCallback() override;
 
     void call(const HeapVector<Member<MutationRecord>>&, MutationObserver*) override;
     ExecutionContext* getExecutionContext() const override { return ContextLifecycleObserver::getExecutionContext(); }
 
     DECLARE_VIRTUAL_TRACE();
 
 private:
     V8MutationCallback(v8::Local<v8::Function>, v8::Local<v8::Object>, ScriptState*);
 
-    static void setWeakCallback(const v8::WeakCallbackInfo<V8MutationCallback>&);
-
     ScopedPersistent<v8::Function> m_callback;
     RefPtr<ScriptState> m_scriptState;
 };
 
 } // namespace blink
 
 #endif // V8MutationCallback_h