@Override
  public void setStateChangeListener(SchedulerStateChangeListener listener) {}
Scheduler invoked by each processor for heartbeating to a row of the table.
Heartbeats every 5 seconds.
The row is determined by the job model version and processor id passed to the scheduler.
All time units are in SECONDS.
samza-azure/src/main/java/org/apache/samza/coordinator/scheduler/HeartbeatScheduler.java