Changes view manager to report visibility and drawn state

mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc

Index: mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc
diff --git a/mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc b/mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc
index 49ba51cdf33bbb035f5e23f87ce4d4e691d7148f..7df75a87c69f3d1b7a40b7b3968f4f0d0fb904e4 100644
--- a/mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc
+++ b/mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc
@@ -365,6 +365,16 @@ void ViewManagerClientImpl::OnViewDeleted(Id view_id) {
     ViewPrivate(view).LocalDestroy();
 }
 
+void ViewManagerClientImpl::OnViewVisibilityChanged(Id view_id, bool visible) {
+  // TODO(sky): implement me.
+  NOTIMPLEMENTED();
+}
+
+void ViewManagerClientImpl::OnViewDrawnStateChanged(Id view_id, bool drawn) {
+  // TODO(sky): implement me.
+  NOTIMPLEMENTED();
+}
+
 void ViewManagerClientImpl::OnViewInputEvent(
     Id view_id,
     EventPtr event,