Remove some unused functions in core

Source/core/clipboard/DataTransfer.h

 /*
  * Copyright (C) 2001 Peter Kelly (pmk@post.com)
  * Copyright (C) 2001 Tobias Anton (anton@stud.fbi.fh-darmstadt.de)
  * Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2008 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 76 matching lines @@
     void setDragImageResource(ImageResource*, const IntPoint&);
     Node* dragImageElement() const { return m_dragImageElement.get(); }
     void setDragImageElement(Node*, const IntPoint&);
 
     PassOwnPtr<DragImage> createDragImage(IntPoint& dragLocation, LocalFrame*) const;
     void declareAndWriteDragImage(Element*, const KURL&, const String& title);
     void writeURL(const KURL&, const String&);
     void writeRange(Range*, LocalFrame*);
     void writePlainText(const String&);
 
-    bool hasData();
-
     void setAccessPolicy(DataTransferAccessPolicy);
     bool canReadTypes() const;
     bool canReadData() const;
     bool canWriteData() const;
     // Note that the spec doesn't actually allow drag image modification outside the dragstart
     // event. This capability is maintained for backwards compatiblity for ports that have
     // supported this in the past. On many ports, attempting to set a drag image outside the
     // dragstart operation is a no-op anyway.
     bool canSetDragImage() const;
 
@@ skipping 29 matching lines @@
     ResourcePtr<ImageResource> m_dragImage;
     RefPtrWillBeMember<Node> m_dragImageElement;
 };
 
 DragOperation convertDropZoneOperationToDragOperation(const String& dragOperation);
 String convertDragOperationToDropZoneOperation(DragOperation);
 
 } // namespace blink
 
 #endif // DataTransfer_h