Revert "Revert 253606 "Revert 251238 "cc: Clean up iterator template to ...""

cc/layers/layer_iterator_unittest.cc

Index: cc/layers/layer_iterator_unittest.cc
diff --git a/cc/layers/layer_iterator_unittest.cc b/cc/layers/layer_iterator_unittest.cc
index 61d7a6151df245006f6488ea14ba5a64ac68335c..c781d28b13fe23e21e6f3451813cbb7922f74374 100644
--- a/cc/layers/layer_iterator_unittest.cc
+++ b/cc/layers/layer_iterator_unittest.cc
@@ -50,7 +50,10 @@ class TestLayer : public Layer {
   EXPECT_EQ(contrib, layer->count_representing_contributing_surface_);         \
   EXPECT_EQ(itself, layer->count_representing_itself_);
 
-typedef LayerIterator<Layer> FrontToBack;
+typedef LayerIterator<Layer,
+                      RenderSurfaceLayerList,
+                      RenderSurface,
+                      LayerIteratorActions::FrontToBack> FrontToBack;
 
 void ResetCounts(RenderSurfaceLayerList* render_surface_layer_list) {
   for (unsigned surface_index = 0;