Make cc output surface creation async

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 c9927be8bc71ad16ebdaa7c3c584606a4a1a4c38..05e4fc55c606722bc039de888584e06c0fdbb71b 100644
--- a/cc/test/layer_tree_test.cc
+++ b/cc/test/layer_tree_test.cc
@@ -290,9 +290,8 @@ class LayerTreeHostClientForTesting : public LayerTreeHostClient,
                                      top_controls_delta);
   }
 
-  virtual scoped_ptr<OutputSurface> CreateOutputSurface(bool fallback)
-      OVERRIDE {
-    return test_hooks_->CreateOutputSurface(fallback);
+  virtual void RequestNewOutputSurface(bool fallback) OVERRIDE {
+    test_hooks_->RequestNewOutputSurface(fallback);
   }
 
   virtual void DidInitializeOutputSurface() OVERRIDE {
@@ -667,6 +666,10 @@ void LayerTreeTest::RunTestWithImplSidePainting() {
   RunTest(true, false, true);
 }
 
+void LayerTreeTest::RequestNewOutputSurface(bool fallback) {
+  layer_tree_host_->SetOutputSurface(CreateOutputSurface(fallback));
+}
+
 scoped_ptr<OutputSurface> LayerTreeTest::CreateOutputSurface(bool fallback) {
   scoped_ptr<FakeOutputSurface> output_surface =
       CreateFakeOutputSurface(fallback);