cc: Defer first OutputSurface creation until client is ready

cc/test/layer_tree_test.cc

Index: cc/test/layer_tree_test.cc
diff --git a/cc/test/layer_tree_test.cc b/cc/test/layer_tree_test.cc
index 64c3e9a3a1a8cc2de59955f98b77b7866ea33dd0..95758c2af1ece29752c516d19eaec11b7f0132e9 100644
--- a/cc/test/layer_tree_test.cc
+++ b/cc/test/layer_tree_test.cc
@@ -293,12 +293,10 @@ class LayerTreeHostForTesting : public LayerTreeHost {
       scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner) {
     scoped_ptr<LayerTreeHostForTesting> layer_tree_host(
         new LayerTreeHostForTesting(test_hooks, client, settings));
-    bool success;
     if (impl_task_runner.get())
-      success = layer_tree_host->InitializeThreaded(impl_task_runner);
+      layer_tree_host->InitializeThreaded(impl_task_runner);
     else
-      success = layer_tree_host->InitializeSingleThreaded(client);
-    EXPECT_TRUE(success);
+      layer_tree_host->InitializeSingleThreaded(client);
     return layer_tree_host.Pass();
   }
 
@@ -463,6 +461,10 @@ void LayerTreeTest::PostSetNextCommitForcesRedrawToMainThread() {
                  main_thread_weak_ptr_));
 }
 
+void LayerTreeTest::WillBeginTest() {
+  layer_tree_host_->SetLayerTreeHostClientReady();
+}
+
 void LayerTreeTest::DoBeginTest() {
   client_ = LayerTreeHostClientForTesting::Create(this);
 
@@ -477,7 +479,7 @@ void LayerTreeTest::DoBeginTest() {
   started_ = true;
   beginning_ = true;
   SetupTree();
-  layer_tree_host_->SetLayerTreeHostClientReady();
+  WillBeginTest();
   BeginTest();
   beginning_ = false;
   if (end_when_begin_returns_)