cc: Clean up iterator template to only take 1 parameter.

cc/trees/layer_tree_host_common.cc

Index: cc/trees/layer_tree_host_common.cc
diff --git a/cc/trees/layer_tree_host_common.cc b/cc/trees/layer_tree_host_common.cc
index 41f7ee72abb50c3ea08aca51138390b62079430c..c1bc1a12c4dff940fccb6e5f4c4bbb2e89d79213 100644
--- a/cc/trees/layer_tree_host_common.cc
+++ b/cc/trees/layer_tree_host_common.cc
@@ -2324,12 +2324,8 @@ LayerImpl* LayerTreeHostCommon::FindLayerThatIsHitByPoint(
     const LayerImplList& render_surface_layer_list) {
   LayerImpl* found_layer = NULL;
 
-  typedef LayerIterator<LayerImpl,
-                        LayerImplList,
-                        RenderSurfaceImpl,
-                        LayerIteratorActions::FrontToBack> LayerIteratorType;
+  typedef LayerIterator<LayerImpl> LayerIteratorType;
   LayerIteratorType end = LayerIteratorType::End(&render_surface_layer_list);
-
   for (LayerIteratorType
            it = LayerIteratorType::Begin(&render_surface_layer_list);
        it != end;