message: Pull the theme through the default process
  This is to ensure the `config` level is respected.
diff: @@ -891,7 +891,7 @@ module.exports = React.createClass({
  */
  _onSetTheme: function(theme) {
  if (!theme) {
  - theme = SettingsStore.getValueAt(SettingLevel.DEFAULT, "theme");
  + theme = SettingsStore.getValue("theme");
  }
  // look for the stylesheet elements.
  