cc: Setup API to release OutputSurface from LTHClient.

cc/trees/layer_tree_host.cc

 // Copyright 2011 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 "cc/trees/layer_tree_host.h"
 
 #include <algorithm>
 #include <stack>
 #include <string>
 
@@ skipping 378 matching lines @@
 }
 
 void LayerTreeHost::SetOutputSurface(scoped_ptr<OutputSurface> surface) {
   TRACE_EVENT0("cc", "LayerTreeHost::SetOutputSurface");
   DCHECK(output_surface_lost_);
   DCHECK(surface);
 
   proxy_->SetOutputSurface(surface.Pass());
 }
 
+scoped_ptr<OutputSurface> LayerTreeHost::ReleaseOutputSurface() {
+  DCHECK(!visible_);
+  DCHECK(!output_surface_lost_);
+
+  output_surface_lost_ = true;

[danakj, 2015/09/17 18:43:55]

rather than doing this directly here, could this function call
DidLoseOutputSurface?

+  return proxy_->ReleaseOutputSurface();
+}
+
 void LayerTreeHost::RequestNewOutputSurface() {
   client_->RequestNewOutputSurface();
 }
 
 void LayerTreeHost::DidInitializeOutputSurface() {
   output_surface_lost_ = false;
   client_->DidInitializeOutputSurface();
 }
 
 void LayerTreeHost::DidFailToInitializeOutputSurface() {
@@ skipping 833 matching lines @@
   return animation_host_ ? animation_host_->HasAnyAnimation(layer->id())
                          : false;
 }
 
 bool LayerTreeHost::HasActiveAnimation(const Layer* layer) const {
   return animation_host_ ? animation_host_->HasActiveAnimation(layer->id())
                          : false;
 }
 
 }  // namespace cc