message: Cleared timer before creating new one
  Otherwise timers hang around and overfire and even fire after unmounted
diff: @@ -39,7 +39,10 @@ class Scene extends React.Component<SceneProps, SceneState> {
  return navigationEvent !== this.state.navigationEvent || this.fluentPeekable();
  }
  componentDidUpdate() {
  - if (this.fluentPeekable()) this.timer = setTimeout(this.peekNavigate);
  + if (this.fluentPeekable()) {
  + clearTimeout(this.timer);
  + this.timer = setTimeout(this.peekNavigate);
  + }
  }
  componentWillUnmount() {
  var {stateNavigator} = this.props.navigationEvent;
  