Implement aura::WindowPortMus::CreateCompositorFrameSink()

services/ui/ws/window_server.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_server.h"
 
 #include <set>
 #include <string>
 
 #include "base/logging.h"
@@ skipping 836 matching lines @@
     // part of a WindowTree. Send the SurfaceId directly to FrameGenerator and
     // claim the temporary reference for the display root.
     display->platform_display()->GetFrameGenerator()->OnSurfaceCreated(
         surface_info);
     display->root_window()
         ->GetOrCreateCompositorFrameSinkManager()
         ->ClaimTemporaryReference(surface_info.id());
     return;
   }
 
   HandleTemporaryReferenceForNewSurface(surface_info.id(), window);

[Fady Samuel, 2017/05/18 20:02:01]

This breaks right? If the embedder is top most (Ash?) then this code fails?

[Peng, 2017/05/18 20:50:59]

I tested it with mushrome, mustash, and mustash + enable_surface_sync. I didn't
see any problem. I don't understand why it breaks. Could you please explain it?

[Fady Samuel, 2017/05/18 20:56:22]

Do we assign an owner to the temporary reference? Is ClaimTemporaryReference
getting called?

[Peng, 2017/05/23 18:00:42]

Done.

 
-  if (!window->parent())
-    return;
+  ClientSpecificId window_tree_id = window->id().client_id;
+  // If the window has a parent, we should use the parent's tree, because the
+  // window could be an embedded window, and the window will be in both
+  // the embedder's tree and embeddee's tree, in this case we shold notify
+  // the embedder's tree about the surface change.
+  if (window->parent())
+    window_tree_id = window->parent()->id().client_id;
 
-  WindowTree* window_tree = GetTreeWithId(window->parent()->id().client_id);
+  WindowTree* window_tree = GetTreeWithId(window_tree_id);
   if (window_tree)
     window_tree->ProcessWindowSurfaceChanged(window, surface_info);
 }
 
 void WindowServer::OnActiveUserIdChanged(const UserId& previously_active_id,
                                          const UserId& active_id) {
 }
 
 void WindowServer::OnUserIdAdded(const UserId& id) {
   activity_monitor_map_[id] = base::MakeUnique<UserActivityMonitor>(nullptr);
 }
 
 void WindowServer::OnUserIdRemoved(const UserId& id) {
   activity_monitor_map_.erase(id);
 }
 
 }  // namespace ws
 }  // namespace ui