dispose method
void
dispose()
Disposes the registry.
Implementation
void dispose() {
_disposeStreamController?.add(null);
_disposeStreamController?.close();
_disposeStreamController = null;
_parentDisposeStreamSubscription?.cancel();
_parentDisposeStreamSubscription = null;
_parentValueStreamSubscription?.cancel();
_parentValueStreamSubscription = null;
_valueStreamController?.close();
_valueStreamController = null;
}