Move ReferencedSurfaceTracker into GpuCompositorFrameSink.

cc/ipc/display_compositor.mojom

 // Copyright 2016 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.
 
 module cc.mojom;
 
 import "cc/ipc/frame_sink_id.mojom";
 import "cc/ipc/mojo_compositor_frame_sink.mojom";
 import "cc/ipc/surface_id.mojom";
 import "cc/ipc/surface_info.mojom";
@@ skipping 43 matching lines @@
       cc.mojom.MojoCompositorFrameSink& compositor_frame_sink,
       cc.mojom.MojoCompositorFrameSinkPrivate& compositor_frame_sink_private,
       cc.mojom.MojoCompositorFrameSinkClient compositor_frame_sink_client);
 };
 
 // The DisplayCompositorClient interface is implemented by the Display
 // Compositor Host, a stable, and privileged peer service to the display
 // compositor. The display compositor host is either the browser process in
 // Chrome or the window server process.
 interface DisplayCompositorClient {
-  // Called by the display compostor when it is created. Provides the top level
-  // root surface id that should reference display roots. This will always be
-  // the first message sent.
-  OnDisplayCompositorCreated(cc.mojom.SurfaceId root_surface_id);
-
   // Called by the display compositor immediately upon receiving a
   // CompositorFrame with a new SurfaceId for the first time.
   OnSurfaceCreated(SurfaceInfo surface_info);
 };