code: public synchronized void sendEvaluatorStatus(
        final ReefServiceProtos.EvaluatorStatusProto evaluatorStatusProto) {
      this.sendHeartBeat(EvaluatorRuntimeProtocol.EvaluatorHeartbeatProto.newBuilder()
          .setTimestamp(System.currentTimeMillis())
          .setEvaluatorStatus(evaluatorStatusProto)
          .build());
    }
docs: Called with a specific EvaluatorStatus that must be delivered to the driver.