Avoid return warning.
Avoid return warning.

threeDart/three.dart,james-storey/three.dart,threeDart/three.dart,hirosuke999/three.dart,hirosuke999/three.dart,threeDart/three.dart,james-storey/three.dart,brason/three.dart,brason/three.dart,hirosuke999/three.dart,brason/three.dart