private WALActionsListener getWALEventTrackerListener(Configuration conf) {
    if (conf.getBoolean(WAL_EVENT_TRACKER_ENABLED_KEY, WAL_EVENT_TRACKER_ENABLED_DEFAULT)) {
      WALEventTrackerListener listener =
        new WALEventTrackerListener(conf, getNamedQueueRecorder(), getServerName());
      return listener;
    }
    return null;
  }
Setup WAL log and replication if enabled. Replication setup is done in here because it wants to
be hooked up to WAL.
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java