static void onSchedule(Job job) {
    // Stop if running
    synchronized (callbacks) {
      SimpleArrayMap<String, JobCallback> jobs = callbacks.get(job.getService());
      if (jobs == null) { // not running
        return;
      }
      JobCallback jobCallback = jobs.get(job.getTag());
      if (jobCallback == null) { // not running
        return;
      }
    }
    JobInvocation key =
        new JobInvocation.Builder()
            .setTag(job.getTag())
            .setService(job.getService())
            .setTrigger(job.getTrigger())
            .build();
    ExecutionDelegator.stopJob(key, false /* must not send the result */);
  }
Stops the job if it is running.

<p>Needed to avoid possibility of sending job result before the reschedule request is received
by Google Play services.
jobdispatcher/src/main/java/com/firebase/jobdispatcher/GooglePlayReceiver.java