code: function(controller) {
        // TODO listening?
        this.__ul.removeChild(controller.__li);
        this.__controllers.splice(this.__controllers.indexOf(controller), 1);
        const _this = this;
        common.defer(function() {
          _this.onResize();
        });
      }
docs: Removes the given controller from the GUI.
  @param {Controller} controller
  @instance