code: public JobStatus asCancelled() {
      return new JobStatus(jobId, description, JobState.CANCELLED, progress, status, eventId);
    }
docs: Creates a copy of this <code>JobStatus</code> with the state set to
  {@link JobState#CANCELLED}.
  @return A copy of this <code>JobStatus</code> with the state set to
  {@link JobState#CANCELLED}.