Add/remove surface references via MojoCompositorFrameSink.

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 495 matching lines @@
 WindowManagerState* WindowServer::GetWindowManagerStateForUser(
     const UserId& user_id) {
   return window_manager_window_tree_factory_set_.GetWindowManagerStateForUser(
       user_id);
 }
 
 cc::mojom::DisplayCompositor* WindowServer::GetDisplayCompositor() {
   return display_compositor_.get();
 }
 
+const cc::SurfaceId& WindowServer::GetRootSurfaceId() const {
+  DCHECK(!root_surface_id_.local_frame_id().nonce().is_empty());
+  return root_surface_id_;
+}
+
 bool WindowServer::GetFrameDecorationsForUser(
     const UserId& user_id,
     mojom::FrameDecorationValuesPtr* values) {
   WindowManagerState* window_manager_state =
       window_manager_window_tree_factory_set_.GetWindowManagerStateForUser(
           user_id);
   if (!window_manager_state)
     return false;
   if (values && window_manager_state->got_frame_decoration_values())
     *values = window_manager_state->frame_decoration_values().Clone();
@@ skipping 274 matching lines @@
       !window->parent()) {
     return;
   }
   WindowTree* window_tree = GetTreeWithId(window->parent()->id().client_id);
   if (window_tree) {
     window_tree->ProcessWindowSurfaceChanged(window, surface_id, frame_size,
                                              device_scale_factor);
   }
 }
 
+void WindowServer::OnRootSurfaceId(const cc::SurfaceId& root_surface_id) {
+  LOG(ERROR) << "Got root surface id " << root_surface_id;
+  root_surface_id_ = root_surface_id;
+}
+
 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