protected static Tool doMROnTableTest(HBaseTestingUtil util, String family, String data,
    String[] args, int valueMultiplier) throws Exception {
    return doMROnTableTest(util, family, data, args, valueMultiplier, -1);
  }
Force use of combiner in doMROnTableTest. Boolean. Default is true.
hbase-mapreduce/src/test/java/org/apache/hadoop/hbase/mapreduce/TestImportTSVWithVisibilityLabels.java