Move BaseDropTarget and BaseDragSource from base to app/win. Remove the "Base...

base/base_drag_source.h

-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef BASE_BASE_DRAG_SOURCE_H_
-#define BASE_BASE_DRAG_SOURCE_H_
-#pragma once
-
-#include <objidl.h>
-
-#include "base/basictypes.h"
-#include "base/ref_counted.h"
-
-///////////////////////////////////////////////////////////////////////////////
-//
-// BaseDragSource
-//
-//  A base IDropSource implementation. Handles notifications sent by an active
-//  drag-drop operation as the user mouses over other drop targets on their
-//  system. This object tells Windows whether or not the drag should continue,
-//  and supplies the appropriate cursors.
-//
-class BaseDragSource : public IDropSource,
-                       public base::RefCountedThreadSafe<BaseDragSource> {
- public:
-  BaseDragSource();
-  virtual ~BaseDragSource() { }
-
-  // Stop the drag operation at the next chance we get.  This doesn't
-  // synchronously stop the drag (since Windows is controlling that),
-  // but lets us tell Windows to cancel the drag the next chance we get.
-  void CancelDrag() {
-    cancel_drag_ = true;
-  }
-
-  // IDropSource implementation:
-  HRESULT __stdcall QueryContinueDrag(BOOL escape_pressed, DWORD key_state);
-  HRESULT __stdcall GiveFeedback(DWORD effect);
-
-  // IUnknown implementation:
-  HRESULT __stdcall QueryInterface(const IID& iid, void** object);
-  ULONG __stdcall AddRef();
-  ULONG __stdcall Release();
-
- protected:
-  virtual void OnDragSourceCancel() { }
-  virtual void OnDragSourceDrop() { }
-  virtual void OnDragSourceMove() { }
-
- private:
-  // Set to true if we want to cancel the drag operation.
-  bool cancel_drag_;
-
-  DISALLOW_COPY_AND_ASSIGN(BaseDragSource);
-};
-
-#endif  // BASE_BASE_DRAG_SOURCE_H_