aura-mus: add a drag representation image.

ui/aura/mus/window_tree_client.cc

 // Copyright 2014 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/aura/mus/window_tree_client.h"
 
 #include <stddef.h>
 
 #include <string>
 #include <utility>
@@ skipping 1467 matching lines @@
 void WindowTreeClient::WmClientJankinessChanged(ClientSpecificId client_id,
                                                 bool janky) {
   if (window_manager_delegate_) {
     auto it = embedded_windows_.find(client_id);
     CHECK(it != embedded_windows_.end());
     window_manager_delegate_->OnWmClientJankinessChanged(
         embedded_windows_[client_id], janky);
   }
 }
 
+void WindowTreeClient::WmBuildDragImage(const gfx::Point& cursor_location,
+                                        const SkBitmap& drag_image,
+                                        const gfx::Vector2d& drag_image_offset,
+                                        ui::mojom::DragEventSource source) {
+  if (!window_manager_delegate_)
+    return;
+
+  window_manager_delegate_->OnWmBuildDragImage(cursor_location, drag_image,
+                                               drag_image_offset, source);
+}
+
+void WindowTreeClient::WmMoveDragImage(
+    const gfx::Point& cursor_location,
+    const WmMoveDragImageCallback& callback) {
+  if (!window_manager_delegate_) {
+    callback.Run();
+    return;
+  }
+
+  window_manager_delegate_->OnWmMoveDragImage(cursor_location);
+  callback.Run();
+}
+
+void WindowTreeClient::WmDestroyDragImage() {
+  if (!window_manager_delegate_)
+    return;
+
+  window_manager_delegate_->OnWmDestroyDragImage();
+}
+
 void WindowTreeClient::WmPerformMoveLoop(uint32_t change_id,
                                          Id window_id,
                                          ui::mojom::MoveLoopSource source,
                                          const gfx::Point& cursor_location) {
   if (!window_manager_delegate_ || current_wm_move_loop_change_ != 0) {
     OnWmMoveLoopCompleted(change_id, false);
     return;
   }
 
   current_wm_move_loop_change_ = change_id;
@@ skipping 373 matching lines @@
   return ScheduleInFlightChange(base::MakeUnique<InFlightCaptureChange>(
       this, capture_synchronizer_.get(), window));
 }
 
 uint32_t WindowTreeClient::CreateChangeIdForFocus(WindowMus* window) {
   return ScheduleInFlightChange(base::MakeUnique<InFlightFocusChange>(
       this, focus_synchronizer_.get(), window));
 }
 
 }  // namespace aura