cc: Set up the framework to restrict access to Layer internals.

cc/layers/texture_layer.cc

Index: cc/layers/texture_layer.cc
diff --git a/cc/layers/texture_layer.cc b/cc/layers/texture_layer.cc
index eab540ecb9743cb087a6e48ae2586e2c6b96a94f..7d1e14229eb40d34b8d58f648181491170d81cd9 100644
--- a/cc/layers/texture_layer.cc
+++ b/cc/layers/texture_layer.cc
@@ -201,7 +201,7 @@ bool TextureLayer::Update() {
   // SetTextureMailbox could be called externally and the same mailbox used for
   // different textures.  Such callers notify this layer that the texture has
   // changed by calling SetNeedsDisplay, so check for that here.
-  return updated || !update_rect_.IsEmpty();
+  return updated || !update_rect().IsEmpty();
 }
 
 void TextureLayer::PushPropertiesTo(LayerImpl* layer) {