Implement temporary reference assignment with DisplayCompositor.

services/ui/ws/server_window_compositor_frame_sink_manager.h

 // Copyright 2015 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.
 
 #ifndef SERVICES_UI_WS_SERVER_WINDOW_COMPOSITOR_FRAME_SINK_MANAGER_H_
 #define SERVICES_UI_WS_SERVER_WINDOW_COMPOSITOR_FRAME_SINK_MANAGER_H_
 
 #include "base/macros.h"
 #include "cc/ipc/compositor_frame.mojom.h"
 #include "cc/ipc/display_compositor.mojom.h"
@@ skipping 44 matching lines @@
   // Adds the provided |frame_sink_id| to this ServerWindow's associated
   // CompositorFrameSink if possible. If this ServerWindow does not have
   // an associated CompositorFrameSink then this method will recursively
   // walk up the window hierarchy and register itself with the first ancestor
   // that has a CompositorFrameSink of the same type. This method returns
   // the FrameSinkId that is the first composited ancestor of the ServerWindow
   // assocaited with the provided |frame_sink_id|.
   void AddChildFrameSinkId(const cc::FrameSinkId& frame_sink_id);
   void RemoveChildFrameSinkId(const cc::FrameSinkId& frame_sink_id);
 
+  // Claims this FrameSinkId will embed |surface_id| so it should own the
+  // temporary reference to |surface_id|.
+  void ClaimTemporaryReference(const cc::SurfaceId& surface_id);
+
   void OnRootChanged(ServerWindow* old_root, ServerWindow* new_root);
 
  private:
   friend class ServerWindowCompositorFrameSinkManagerTestApi;
   friend class ServerWindowCompositorFrameSink;
 
-  ServerWindow* window_;
+  void CreateCompositorFrameSinkData();
+
+  ServerWindow* const window_;
 
   std::unique_ptr<CompositorFrameSinkData> frame_sink_data_;
 
   DISALLOW_COPY_AND_ASSIGN(ServerWindowCompositorFrameSinkManager);
 };
 
 }  // namespace ws
 }  // namespace ui
 
 #endif  // SERVICES_UI_WS_SERVER_WINDOW_COMPOSITOR_FRAME_SINK_MANAGER_H_