cc: Restructure access to LayerTreeHost in LayerTreeTests.

cc/test/layer_tree_test.h

Index: cc/test/layer_tree_test.h
diff --git a/cc/test/layer_tree_test.h b/cc/test/layer_tree_test.h
index e55e2ee2cd8b076925c2d673106709f5d4dbb8ae..4acc90f05f85f299032e494aab97cb8775863473 100644
--- a/cc/test/layer_tree_test.h
+++ b/cc/test/layer_tree_test.h
@@ -143,7 +143,8 @@ class LayerTreeTest : public testing::Test, public TestHooks {
   }
   bool TestEnded() const { return ended_; }
 
-  LayerTreeHostInProcess* layer_tree_host();
+  LayerTreeHost* layer_tree_host();
+  LayerTreeHostInProcess* layer_tree_host_in_process();
   LayerTree* layer_tree() { return layer_tree_host()->GetLayerTree(); }
   SharedBitmapManager* shared_bitmap_manager() const {
     return shared_bitmap_manager_.get();