cc: Setup API to release OutputSurface from LTHClient.

content/renderer/gpu/render_widget_compositor.cc

 // Copyright (c) 2013 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 "content/renderer/gpu/render_widget_compositor.h"
 
 #include <limits>
 #include <string>
 
 #include "base/command_line.h"
@@ skipping 197 matching lines @@
   return compositor;
 }
 
 RenderWidgetCompositor::RenderWidgetCompositor(
     RenderWidget* widget,
     CompositorDependencies* compositor_deps)
     : num_failed_recreate_attempts_(0),
       widget_(widget),
       compositor_deps_(compositor_deps),
       layout_and_paint_async_callback_(nullptr),
-      weak_factory_(this) {
-}
+      did_give_back_output_surface_(false),
+      weak_factory_(this) {}
 
 void RenderWidgetCompositor::Initialize() {
   base::CommandLine* cmd = base::CommandLine::ForCurrentProcess();
 
   cc::LayerTreeSettings settings;
 
   // For web contents, layer transforms should scale up the contents of layers
   // to keep content always crisp when possible.
   settings.layer_transforms_should_scale_layer_contents = true;
 
@@ skipping 719 matching lines @@
   // Tolerate a certain number of recreation failures to work around races
   // in the output-surface-lost machinery.
   LOG_IF(FATAL, (num_failed_recreate_attempts_ >= MAX_OUTPUT_SURFACE_RETRIES))
       << "Failed to create a fallback OutputSurface.";
 
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&RenderWidgetCompositor::RequestNewOutputSurface,
                             weak_factory_.GetWeakPtr()));
 }
 
+scoped_ptr<cc::OutputSurface> RenderWidgetCompositor::GiveBackOutputSurface() {
+  did_give_back_output_surface_ = true;

[sohanjg, 2015/08/12 10:50:29]

i have added this member to reflect the compositor's state. But couldnt find any
uasge.

+  num_failed_recreate_attempts_ = 0;
+  layer_tree_host_->SetVisible(false);
+  return layer_tree_host_->GetOutputSurface().Pass();
+}
+
 void RenderWidgetCompositor::WillCommit() {
   InvokeLayoutAndPaintCallback();
 }
 
 void RenderWidgetCompositor::DidCommit() {
   DCHECK(!temporary_copy_output_request_);
   widget_->DidCommitCompositorFrame();
   compositor_deps_->GetRendererScheduler()->DidCommitFrameToCompositor();
 }
 
@@ skipping 65 matching lines @@
     return;
   provider->ContextGL()->RateLimitOffscreenContextCHROMIUM();
 }
 
 void RenderWidgetCompositor::SetSurfaceIdNamespace(
     uint32_t surface_id_namespace) {
   layer_tree_host_->set_surface_id_namespace(surface_id_namespace);
 }
 
 }  // namespace content