@Override
 public <T> Subscription schedule(
     T state,
     Func2<? super Scheduler, ? super T, ? extends Subscription> action,
     long delayTime,
     TimeUnit unit) {
   return actual.schedule(state, action, delayTime, unit);
 }
 @Override
 public <T> Subscription schedule(
     T state, Func2<? super Scheduler, ? super T, ? extends Subscription> action) {
   return actual.schedule(state, action);
 }
 private CurrentThreadScheduler() {
   actual = rx.schedulers.CurrentThreadScheduler.getInstance();
 }