code: @CheckReturnValue
      @SchedulerSupport(SchedulerSupport.NONE)
      @BackpressureSupport(BackpressureKind.UNBOUNDED_IN)
      public final <U, V> Maybe<T> delay(Publisher<U> delayIndicator) {
          ObjectHelper.requireNonNull(delayIndicator, "delayIndicator is null");
          return RxJavaPlugins.onAssembly(new MaybeDelayOtherPublisher<T, U>(this, delayIndicator));
      }
docs: Delays the emission of this Maybe until the given Publisher signals an item or completes.
  <p>
  <img width="640" height="450" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/delay.oo.png" alt="">
  <dl>
  <dt><b>Backpressure:</b></dt>
  <dd>The {@code delayIndicator} is consumed in an unbounded manner but is cancelled after
  the first item it produces.</dd>
  <dt><b>Scheduler:</b></dt>
  <dd>This version of {@code delay} does not operate by default on a particular {@link Scheduler}.</dd>
  </dl>
  
  @param <U>
  the subscription delay value type (ignored)
  @param <V>
  the item delay value type (ignored)
  @param delayIndicator
  the Publisher that gets subscribed to when this Maybe signals an event and that
  signal is emitted when the Publisher signals an item or completes
  @return the new Maybe instance
  @see <a href="http://reactivex.io/documentation/operators/delay.html">ReactiveX operators documentation: Delay</a>