Implement aura::WindowPortMus::CreateCompositorFrameSink()

services/ui/ws/window_tree.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 "services/ui/ws/window_tree.h"
 
 #include <stddef.h>
 
 #include <utility>
 
@@ skipping 933 matching lines @@
       !IsWindowKnown(transient_window, &transient_client_window_id)) {
     return;
   }
   client()->OnTransientWindowRemoved(client_window_id.id,
                                      transient_client_window_id.id);
 }
 
 void WindowTree::ProcessWindowSurfaceChanged(
     ServerWindow* window,
     const cc::SurfaceInfo& surface_info) {
-  ServerWindow* parent_window = window->parent();
-  ClientWindowId client_window_id, parent_client_window_id;
-  if (!IsWindowKnown(window, &client_window_id) ||
-      !IsWindowKnown(parent_window, &parent_client_window_id) ||
-      !created_window_map_.count(parent_window->id())) {
+  ClientWindowId client_window_id;
+  if (!IsWindowKnown(window, &client_window_id))
     return;
-  }
-
   client()->OnWindowSurfaceChanged(client_window_id.id, surface_info);
 }
 
 void WindowTree::SendToPointerWatcher(const ui::Event& event,
                                       ServerWindow* target_window,
                                       int64_t display_id) {
   if (!EventMatchesPointerWatcher(event))
     return;
 
   ClientWindowId client_window_id;
@@ skipping 1530 matching lines @@
   client()->OnCompleteDrop(client_window_id.id, event_flags, cursor_offset,
                            effect_bitmask, callback);
 }
 
 void WindowTree::PerformOnDragDropDone() {
   client()->OnDragDropDone();
 }
 
 }  // namespace ws
 }  // namespace ui