code: public void unregisterDereferencedListener(Provider.DereferenceListener dereferenceListener) {
          if (dereferenceListeners != null) {
              dereferenceListeners.remove(dereferenceListener);
              if (dereferenceListeners.isEmpty()) {
                  dereferenceListeners = null;
              }
          }
      }
docs: Unregister {@link Provider.DereferenceListener} which will be called when the provider's
  instance is dereferenced.
  
  @param dereferenceListener The listener