cc: Move render surface ownership from layers to the effect tree

cc/layers/layer_impl.h

Index: cc/layers/layer_impl.h
diff --git a/cc/layers/layer_impl.h b/cc/layers/layer_impl.h
index 5fff96cb82cd740d73cfb6dfc542a6d9703d8ce7..5729664bead061bc3b1d4710eba11d23df84a7db 100644
--- a/cc/layers/layer_impl.h
+++ b/cc/layers/layer_impl.h
@@ -233,13 +233,7 @@ class CC_EXPORT LayerImpl {
 
   bool ShowDebugBorders() const;
 
-  // These invalidate the host's render surface layer list.  The caller
-  // is responsible for calling set_needs_update_draw_properties on the tree
-  // so that its list can be recreated.
-  void ClearRenderSurfaceLayerList();
-  void SetHasRenderSurface(bool has_render_surface);
-
-  RenderSurfaceImpl* render_surface() const { return render_surface_.get(); }
+  RenderSurfaceImpl* render_surface() const;

[ajuma, 2017/02/21 15:16:50]

This needs to be renamed since it's no longer a trivial getter, but I'd like to
do the renaming in a separate patch since there are lots of callsites (~500) to
change.

 
   // The render surface which this layer draws into. This can be either owned by
   // the same layer or an ancestor of this layer.