async delayDispatchEvent_(event) {
    // Wait until the next interpreter cycle.
    await Promise.resolve();

    // Only dispatch the event if we are still alive.
    if (this.loadMode_ != shaka.Player.LoadMode.DESTROYED) {
      this.dispatchEvent(event);
    }
  }
Fire an event, but wait a little bit so that the immediate execution can
complete before the event is handled.

@param {!shaka.util.FakeEvent} event
@private