CC Animations: Make LayerAnimationController creation optional

cc/test/layer_tree_host_common_test.h

Index: cc/test/layer_tree_host_common_test.h
diff --git a/cc/test/layer_tree_host_common_test.h b/cc/test/layer_tree_host_common_test.h
index d899baba0169989b0476eb8822e76f86437b1c1d..3ae8a3f1de7d7f278cfae86addf62d25cd6992ea 100644
--- a/cc/test/layer_tree_host_common_test.h
+++ b/cc/test/layer_tree_host_common_test.h
@@ -10,6 +10,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "cc/layers/layer_lists.h"
 #include "cc/test/fake_layer_tree_host_client.h"
+#include "cc/trees/layer_tree_settings.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace gfx {
@@ -118,9 +119,12 @@ class LayerTreeHostCommonTestBase {
 
   scoped_ptr<FakeLayerTreeHost> CreateFakeLayerTreeHost();
 
+  const LayerSettings& layer_settings() { return layer_settings_; }
+
  private:
   scoped_ptr<RenderSurfaceLayerList> render_surface_layer_list_;
   scoped_ptr<std::vector<LayerImpl*>> render_surface_layer_list_impl_;
+  LayerSettings layer_settings_;
 
   FakeLayerTreeHostClient client_;
   int render_surface_layer_list_count_;