Get drag and drop working for win aura.

ui/views/widget/desktop_aura/desktop_root_window_host_win.h

 // Copyright (c) 2012 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 UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_WIN_H_
 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_WIN_H_
 
 #include "ui/aura/root_window_host.h"
 #include "ui/views/views_export.h"
 #include "ui/views/widget/desktop_aura/desktop_root_window_host.h"
 #include "ui/views/win/hwnd_message_handler_delegate.h"
 
 namespace aura {
 namespace client {
 class DefaultCaptureClient;
 class FocusClient;
 class ScreenPositionClient;
 }
 }
 
 namespace views {
 class DesktopActivationClient;
 class DesktopCursorClient;
 class DesktopDispatcherClient;
+class DesktopDragDropClientWin;
 class HWNDMessageHandler;
 namespace corewm {
 class CompoundEventFilter;
 class InputMethodEventFilter;
 }
 
 class VIEWS_EXPORT DesktopRootWindowHostWin
     : public DesktopRootWindowHost,
       public aura::RootWindowHost,
       public HWNDMessageHandlerDelegate {
@@ skipping 189 matching lines @@
   aura::RootWindowHostDelegate* root_window_host_delegate_;
   aura::Window* content_window_;
 
   // In some cases, we set a screen position client on |root_window_|. If we
   // do, we're responsible for the lifetime.
   scoped_ptr<aura::client::ScreenPositionClient> position_client_;
 
   // A simple cursor client which just forwards events to the RootWindow.
   scoped_ptr<DesktopCursorClient> cursor_client_;
 
+  scoped_ptr<DesktopDragDropClientWin> drag_drop_client_;
+
   // The RootWindow's CompoundEventFilter.
   views::corewm::CompoundEventFilter* root_window_event_filter_;
 
   DISALLOW_COPY_AND_ASSIGN(DesktopRootWindowHostWin);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_WIN_H_