Mus+Ash: Use standard cc mechanism for surface lifetime.

services/ui/ws/platform_display.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/platform_display.h"
 
 #include "base/numerics/safe_conversions.h"
 #include "build/build_config.h"
 #include "cc/ipc/quads.mojom.h"
 #include "cc/output/copy_output_request.h"
@@ skipping 280 matching lines @@
 
 void DefaultPlatformDisplay::RequestCopyOfOutput(
     std::unique_ptr<cc::CopyOutputRequest> output_request) {
   frame_generator_->RequestCopyOfOutput(std::move(output_request));
 }
 
 ServerWindow* DefaultPlatformDisplay::GetRootWindow() {
   return delegate_->GetRootWindow();
 }
 
-void DefaultPlatformDisplay::OnCompositorFrameDrawn() {
-  if (delegate_)
-    delegate_->OnCompositorFrameDrawn();
-}
-
 bool DefaultPlatformDisplay::IsInHighContrastMode() {
   return delegate_ ? delegate_->IsInHighContrastMode() : false;
 }
 
 const ViewportMetrics& DefaultPlatformDisplay::GetViewportMetrics() {
   return metrics_;
 }
 
 }  // namespace ws
 
 }  // namespace ui