cc: Defer first OutputSurface creation until client is ready

cc/trees/single_thread_proxy.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/single_thread_proxy.h"
 
 #include "base/auto_reset.h"
 #include "base/debug/trace_event.h"
 #include "cc/debug/benchmark_instrumentation.h"
 #include "cc/output/context_provider.h"
@@ skipping 26 matching lines @@
       inside_draw_(false) {
   TRACE_EVENT0("cc", "SingleThreadProxy::SingleThreadProxy");
   DCHECK(Proxy::IsMainThread());
   DCHECK(layer_tree_host);
 
   // Impl-side painting not supported without threaded compositing.
   CHECK(!layer_tree_host->settings().impl_side_painting)
       << "Threaded compositing must be enabled to use impl-side painting.";
 }
 
-void SingleThreadProxy::Start(scoped_ptr<OutputSurface> first_output_surface) {
-  DCHECK(first_output_surface);
+void SingleThreadProxy::Start() {
   DebugScopedSetImplThread impl(this);
   layer_tree_host_impl_ = layer_tree_host_->CreateLayerTreeHostImpl(this);
-  first_output_surface_ = first_output_surface.Pass();
 }
 
 SingleThreadProxy::~SingleThreadProxy() {
   TRACE_EVENT0("cc", "SingleThreadProxy::~SingleThreadProxy");
   DCHECK(Proxy::IsMainThread());
   // Make sure Stop() got called or never Started.
   DCHECK(!layer_tree_host_impl_);
 }
 
 bool SingleThreadProxy::CompositeAndReadback(void* pixels, gfx::Rect rect) {
@@ skipping 44 matching lines @@
 
   // Changing visibility could change ShouldComposite().
   UpdateBackgroundAnimateTicking();
 }
 
 void SingleThreadProxy::CreateAndInitializeOutputSurface() {
   TRACE_EVENT0(
       "cc", "SingleThreadProxy::CreateAndInitializeOutputSurface");
   DCHECK(Proxy::IsMainThread());
 
-  scoped_ptr<OutputSurface> output_surface = first_output_surface_.Pass();
-  if (!output_surface)
-    output_surface = layer_tree_host_->CreateOutputSurface();
+  scoped_ptr<OutputSurface> output_surface =
+      layer_tree_host_->CreateOutputSurface();
   if (!output_surface) {
     OnOutputSurfaceInitializeAttempted(false);
     return;
   }
 
   scoped_refptr<cc::ContextProvider> offscreen_context_provider;
   if (created_offscreen_context_provider_) {
     offscreen_context_provider =
         layer_tree_host_->client()->OffscreenContextProvider();
     if (!offscreen_context_provider.get() ||
@@ skipping 413 matching lines @@
 void SingleThreadProxy::DidSwapFrame() {
   if (next_frame_is_newly_committed_frame_) {
     next_frame_is_newly_committed_frame_ = false;
     layer_tree_host_->DidCommitAndDrawFrame();
   }
 }
 
 bool SingleThreadProxy::CommitPendingForTesting() { return false; }
 
 }  // namespace cc