code: private void updateLastMapLocalityLevel(JobInProgress job,
        Task mapTaskLaunched, TaskTrackerStatus tracker) {
      JobInfo info = infos.get(job);
      LocalityLevel localityLevel = localManager.taskToLocalityLevel(
          job, mapTaskLaunched, tracker);
      info.lastMapLocalityLevel = localityLevel;
      info.timeWaitedForLocalMap = 0;
    }
docs: Update a job's locality level and locality wait variables given that that
  it has just launched a map task on a given task tracker.