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 95c44bcfeb1559590cee4f2d1953371d8b35bc17..4daa17bccaf60ba9d67289f100e084d9312ba702 100644
--- a/cc/trees/layer_tree_host_unittest.cc
+++ b/cc/trees/layer_tree_host_unittest.cc
@@ -1976,6 +1976,7 @@ class LayerTreeHostWithProxy : public LayerTreeHost {
                          scoped_ptr<FakeProxy> proxy)
       : LayerTreeHost(client, NULL, settings) {
     proxy->SetLayerTreeHost(this);
+    client->SetLayerTreeHost(this);
     InitializeForTesting(proxy.PassAs<Proxy>());
   }
 };
@@ -2045,6 +2046,7 @@ 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);
@@ -2060,6 +2062,7 @@ 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);
@@ -2075,6 +2078,7 @@ 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());
@@ -2091,6 +2095,7 @@ 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());