aura-mus: wire up drag and drop.

services/ui/ws/drag_controller.h

 // Copyright 2016 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 SERVICES_UI_WS_DRAG_CONTROLLER_H_
 #define SERVICES_UI_WS_DRAG_CONTROLLER_H_
 
 #include <map>
 #include <set>
 
@@ skipping 93 matching lines @@
   void DispatchOperation(ServerWindow* window, WindowState* state);
   void OnRespondToOperation(ServerWindow* window);
 
   // Callback methods.
   void OnDragStatusCompleted(const WindowId& id, DropEffectBitmask bitmask);
   void OnDragDropCompleted(const WindowId& id, DropEffect action);
 
   // ServerWindowObserver:
   void OnWindowDestroying(ServerWindow* window) override;
 
+  static std::string ToString(OperationType type);
+
   // Our owner.
   DragSource* source_;
 
   // Object to notify about all cursor changes.
   DragCursorUpdater* cursor_updater_;
 
   // A bit-field of acceptable drag operations offered by the source.
   const DropEffectBitmask drag_operations_;
 
   // Only act on pointer events that meet this id.
@@ skipping 27 matching lines @@
 
   base::WeakPtrFactory<DragController> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DragController);
 };
 
 }  // namespace ws
 }  // namespace ui
 
 #endif  // SERVICES_UI_WS_DRAG_CONTROLLER_H_