public void appendMobMetadata(SetMultimap<TableName, String> mobRefSet) throws IOException {
    liveFileWriter.appendMobMetadata(mobRefSet);
    if (historicalFileWriter != null) {
      historicalFileWriter.appendMobMetadata(mobRefSet);
    }
  }
Appends MOB - specific metadata (even if it is empty)
@param mobRefSet - original table -> set of MOB file names
@throws IOException problem writing to FS
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StoreFileWriter.java