taskDependencyFactory
        );
    }

    @Override
    public void markAsObserved(InternalState requestedState) {
        markThisObserved(requestedState);
        markParentsObserved(requestedState);
    }

    private void markThisObserved(InternalState requestedState) {
        synchronized (observationLock) {
            if (observedState.compareTo(requestedState) < 0) {