Make cc output surface creation async

cc/trees/layer_tree_host_unittest.cc

Index: cc/trees/layer_tree_host_unittest.cc
diff --git a/cc/trees/layer_tree_host_unittest.cc b/cc/trees/layer_tree_host_unittest.cc
index b4b64791629608269688f5b68942194e56e6a330..ca7bc9ef57abdc19ff53602754d0fd9c1985c01a 100644
--- a/cc/trees/layer_tree_host_unittest.cc
+++ b/cc/trees/layer_tree_host_unittest.cc
@@ -1975,6 +1975,7 @@ class LayerTreeHostWithProxy : public LayerTreeHost {
                          scoped_ptr<FakeProxy> proxy)
       : LayerTreeHost(client, NULL, settings) {
     proxy->SetLayerTreeHost(this);
+    client->SetLayerTreeHost(this);
     InitializeForTesting(proxy.PassAs<Proxy>());
   }
 };
@@ -2044,6 +2045,7 @@ TEST(LayerTreeHostTest, PartialUpdatesWithGLRenderer) {
       new TestSharedBitmapManager());
   scoped_ptr<LayerTreeHost> host = LayerTreeHost::CreateSingleThreaded(
       &client, &client, shared_bitmap_manager.get(), settings);
+  client.SetLayerTreeHost(host.get());
   host->Composite(base::TimeTicks::Now());
 
   EXPECT_EQ(4u, host->settings().max_partial_texture_updates);
@@ -2059,6 +2061,7 @@ TEST(LayerTreeHostTest, PartialUpdatesWithSoftwareRenderer) {
       new TestSharedBitmapManager());
   scoped_ptr<LayerTreeHost> host = LayerTreeHost::CreateSingleThreaded(
       &client, &client, shared_bitmap_manager.get(), settings);
+  client.SetLayerTreeHost(host.get());
   host->Composite(base::TimeTicks::Now());
 
   EXPECT_EQ(4u, host->settings().max_partial_texture_updates);
@@ -2074,6 +2077,7 @@ TEST(LayerTreeHostTest, PartialUpdatesWithDelegatingRendererAndGLContent) {
       new TestSharedBitmapManager());
   scoped_ptr<LayerTreeHost> host = LayerTreeHost::CreateSingleThreaded(
       &client, &client, shared_bitmap_manager.get(), settings);
+  client.SetLayerTreeHost(host.get());
   host->Composite(base::TimeTicks::Now());
 
   EXPECT_EQ(0u, host->MaxPartialTextureUpdates());
@@ -2090,6 +2094,7 @@ TEST(LayerTreeHostTest,
       new TestSharedBitmapManager());
   scoped_ptr<LayerTreeHost> host = LayerTreeHost::CreateSingleThreaded(
       &client, &client, shared_bitmap_manager.get(), settings);
+  client.SetLayerTreeHost(host.get());
   host->Composite(base::TimeTicks::Now());
 
   EXPECT_EQ(0u, host->MaxPartialTextureUpdates());