Wires up drag/drop for aura-mus

ui/wm/public/drag_drop_delegate.cc

-// 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.
-
-#include "ui/wm/public/drag_drop_delegate.h"
-
-#include "ui/aura/window.h"
-#include "ui/aura/window_property.h"
-
-DECLARE_WINDOW_PROPERTY_TYPE(aura::client::DragDropDelegate*)
-
-namespace aura {
-namespace client {
-
-DEFINE_LOCAL_WINDOW_PROPERTY_KEY(
-    DragDropDelegate*, kDragDropDelegateKey, NULL);
-
-void SetDragDropDelegate(Window* window, DragDropDelegate* delegate) {
-  window->SetProperty(kDragDropDelegateKey, delegate);
-}
-
-DragDropDelegate* GetDragDropDelegate(Window* window) {
-  return window->GetProperty(kDragDropDelegateKey);
-}
-
-}  // namespace client
-}  // namespace aura