`. e.g.
   *
   * ```js
   * Polymer.AppLayout.scroll({top: 0, behavior: 'smooth'});
   * ```
   *
   * To scroll in a silent mode, without notifying scroll changes to any app-layout elements,
   * you can set the option `behavior: 'silent'`. This is particularly useful we you are using
   * `app-header` and you desire to scroll to the top of a scrolling region without running
   * scroll effects. e.g.
   *
   * ```js
   * Polymer.AppLayout.scroll({top: 0, behavior: 'silent'});
   * ```
   *
   * @param {Ob