cc: Defer first OutputSurface creation until client is ready

cc/trees/thread_proxy.cc

Index: cc/trees/thread_proxy.cc
diff --git a/cc/trees/thread_proxy.cc b/cc/trees/thread_proxy.cc
index 2823182d5908d61b834dba6f53f96d35df8a4a75..0518a6b4440a4c4b1beca46510ef36820d41d376 100644
--- a/cc/trees/thread_proxy.cc
+++ b/cc/trees/thread_proxy.cc
@@ -266,9 +266,8 @@ void ThreadProxy::DoCreateAndInitializeOutputSurface() {
   TRACE_EVENT0("cc", "ThreadProxy::DoCreateAndInitializeOutputSurface");
   DCHECK(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();
 
   RendererCapabilities capabilities;
   bool success = !!output_surface;
@@ -641,10 +640,9 @@ ThreadProxy::contents_texture_manager_on_impl_thread() {
   return contents_texture_manager_unsafe_;
 }
 
-void ThreadProxy::Start(scoped_ptr<OutputSurface> first_output_surface) {
+void ThreadProxy::Start() {
   DCHECK(IsMainThread());
   DCHECK(Proxy::HasImplThread());
-  DCHECK(first_output_surface);
 
   // Create LayerTreeHostImpl.
   DebugScopedSetMainThreadBlocked main_thread_blocked(this);
@@ -657,7 +655,6 @@ void ThreadProxy::Start(scoped_ptr<OutputSurface> first_output_surface) {
   completion.Wait();
 
   main_thread_weak_ptr_ = weak_factory_.GetWeakPtr();
-  first_output_surface_ = first_output_surface.Pass();
 
   started_ = true;
 }