@Override
    protected RSRpcServices createRpcServices() throws IOException {
      return new HeartbeatRPCServices(this);
    }
Custom HRegionServer instance that instantiates {@link HeartbeatRPCServices} in place of
{@link RSRpcServices} to allow us to toggle support for heartbeat messages
hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestScannerHeartbeatMessages.java