Method CountThread

tensorflow/cc/training/coordinator_test.cc:99–106

 private:
  void CountThread(std::atomic<int>* counter, int until, Notification* start) {
    if (start != nullptr) start->WaitForNotification();
    while (!coord_->ShouldStop() && counter->load() < until) {
      (*counter)++;
      Env::Default()->SleepForMicroseconds(10 * 1000);
    }
    coord_->RequestStop().IgnoreError();
  }
  void SetStatusThread(const Status& status, BlockingCounter* counter,
                       Notification* start) {
    start->WaitForNotification();