cc: Consolidate LayerList types.

cc/trees/tree_synchronizer_unittest.cc

Index: cc/trees/tree_synchronizer_unittest.cc
diff --git a/cc/trees/tree_synchronizer_unittest.cc b/cc/trees/tree_synchronizer_unittest.cc
index c402afcc0d2ed36c5494b2dd9e0d63661025f2be..5c9bc9231fd29db11e3d34747a5206d123a4fc3e 100644
--- a/cc/trees/tree_synchronizer_unittest.cc
+++ b/cc/trees/tree_synchronizer_unittest.cc
@@ -119,9 +119,8 @@ void ExpectTreesAreIdentical(Layer* layer,
         layer->replica_layer(), layer_impl->replica_layer(), tree_impl);
   }
 
-  const std::vector<scoped_refptr<Layer> >& layer_children = layer->children();
-  const ScopedPtrVector<LayerImpl>& layer_impl_children =
-      layer_impl->children();
+  const LayerList& layer_children = layer->children();
+  const OwnedLayerImplList& layer_impl_children = layer_impl->children();
 
   ASSERT_EQ(layer_children.size(), layer_impl_children.size());