public <T> void resubscribe(TaggedObserver<? super T> observer) {
    resubscribe(observer, Utils.getObserverTag(observer));
  }
public <T> void resubscribe(TaggedObserver<? super T> observer) {
    resubscribe(observer, Utils.getObserverTag(observer));
  }
public < T > void resubscribe ( TaggedObserver < ? super T > observer ) { resubscribe ( observer , Utils . getObserverTag ( observer ) ) ; }
Resubscribes the {@link TaggedObserver} to the observable
identified by {@code observableTag}.
<p> Convenience method
for {@link #resubscribe(TaggedObserver, String)} when {@code observer} only
is subscribed to one {@link Observable}.
Resubscribes the {