src/main/java/io/reactivex/Completable.java
@CheckReturnValue
    @SchedulerSupport(SchedulerSupport.COMPUTATION)
    public final Completable timeout(long timeout, TimeUnit unit) {
        return timeout0(timeout, unit, Schedulers.computation(), null);
    }
@CheckReturnValue
    @SchedulerSupport(SchedulerSupport.COMPUTATION)
    public final Completable timeout(long timeout, TimeUnit unit) {
        return timeout0(timeout, unit, Schedulers.computation(), null);
    }
Returns a Completable that runs this Completable and emits a TimeoutException in case
this Completable doesn't complete within the given time.
<p>
<img width="640" height="348" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/Completable.timeout.png" alt="">
<dl>
<dt><b>Scheduler:</b></dt>
<dd>{@code timeout} signals the TimeoutException on the {@code computation} {@link Scheduler}.</dd>
</dl>
@param timeout the timeout value
@param unit the timeout unit
@return the new Completable instance
@throws NullPointerException if unit is null