join_counter_ = join_counter;
  }

  void StartCounting(std::atomic<int>* counter, int until,
                     Notification* start = nullptr) {
    thread_pool_->Schedule(
        std::bind(&MockQueueRunner::CountThread, this, counter, until, start));
  }

  void StartSettingStatus(const Status& status, BlockingCounter* counter,
                          Notification* start) {