cc: Make occlusion a draw property.

cc/layers/layer_impl.cc

Index: cc/layers/layer_impl.cc
diff --git a/cc/layers/layer_impl.cc b/cc/layers/layer_impl.cc
index 3795bb4ed8aa060a3cfe3c1c1782a2ed3fd2fa19..6e11644f42cd461f2ce6069dc5ff9426eecf730c 100644
--- a/cc/layers/layer_impl.cc
+++ b/cc/layers/layer_impl.cc
@@ -378,11 +378,6 @@ RenderPassId LayerImpl::NextContributingRenderPassId(RenderPassId id) const {
   return RenderPassId(0, 0);
 }
 
-bool LayerImpl::UpdateTiles(const Occlusion& occlusion_in_layer_space,
-                            bool resourceless_software_draw) {
-  return false;
-}
-
 void LayerImpl::GetContentsResourceId(ResourceProvider::ResourceId* resource_id,
                                       gfx::Size* resource_size) const {
   NOTREACHED();