mus drag and drop: return the completed effect to the caller.

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 "base/memory/weak_ptr.h"
 #include "services/ui/common/types.h"
 #include "services/ui/ws/ids.h"
@@ skipping 34 matching lines @@
   void OnWillDestroyDragTargetConnection(DragTargetConnection* connection);
 
  private:
   friend class test::DragControllerTestApi;
   enum class OperationType { NONE, ENTER, OVER, LEAVE, DROP };
   struct Operation;
   struct WindowState;
 
   // Notifies all windows we messaged that the drag is finished, and then tell
   // |source| the result.
-  void MessageDragCompleted(bool success);
+  void MessageDragCompleted(bool success, uint32_t action_taken);
 
   // Returns the number of events on |window|. A value of 1 means that there's
   // a single event outstanding that we're waiting for a response from the
   // client, all values over 1 are queued and will be dispatched when the event
   // in the front of the queue gets a response.
   size_t GetSizeOfQueueForWindow(ServerWindow* window);
 
   // Sets |current_target_window_| to |current_target|, making sure that we add
   // and release ServerWindow observers correctly.
   void SetCurrentTargetWindow(ServerWindow* current_target);
 
   // Ensure that |window| has an entry in |window_state_| and that we're an
   // observer.
   void EnsureWindowObserved(ServerWindow* window);
 
   void QueueOperation(ServerWindow* window,
                       OperationType type,
                       uint32_t event_flags,
                       gfx::Point screen_position);
   void DispatchOperation(ServerWindow* window, WindowState* state);
   void OnRespondToOperation(ServerWindow* window);
 
   // Callback methods.
   void OnDragStatusCompleted(const WindowId& id, uint32_t bitmask);
-  void OnDragDropCompleted(const WindowId& id, uint32_t bitmask);
+  void OnDragDropCompleted(const WindowId& id, uint32_t action);
 
   // ServerWindowObserver:
   void OnWindowDestroying(ServerWindow* window) override;
 
   // Our owner.
   DragSource* source_;
 
   // A bit-field of acceptable drag operations offered by the source.
   const uint32_t drag_operations_;
 
@@ skipping 25 matching lines @@
 
   base::WeakPtrFactory<DragController> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DragController);
 };
 
 }  // namespace ws
 }  // namespace ui
 
 #endif  // SERVICES_UI_WS_DRAG_CONTROLLER_H_