Revert of [Oilpan] Prepare full definition of classes before using Member

third_party/WebKit/Source/core/page/DragData.h

 /*
  * Copyright (C) 2007 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
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN 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 DragData_h
 #define DragData_h
 
 #include "core/CoreExport.h"
-#include "core/clipboard/DataObject.h"
 #include "core/page/DragActions.h"
 #include "platform/geometry/IntPoint.h"
 #include "platform/heap/Handle.h"
 #include "wtf/Forward.h"
 #include "wtf/HashMap.h"
 #include "wtf/Vector.h"
 
 namespace blink {
 
+class DataObject;
 class DocumentFragment;
 class LocalFrame;
 class Range;
 
 enum DragApplicationFlags {
     DragApplicationNone = 0,
     DragApplicationIsModal = 1,
     DragApplicationIsSource = 2,
     DragApplicationHasAttachedSheet = 4,
     DragApplicationIsCopyKeyDown = 8
@@ skipping 27 matching lines @@
 private:
     IntPoint m_clientPosition;
     IntPoint m_globalPosition;
     Member<DataObject> m_platformDragData;
     DragOperation m_draggingSourceOperationMask;
     DragApplicationFlags m_applicationFlags;
 };
 
 }
 
-#endif // DragData_h
+#endif // !DragData_h