String makeDeltaDirName(long minTxnId, long maxTxnId) {
    if(minTxnId != maxTxnId) {
      //covers both streaming api and post compaction style.
      return makeDeltaDirNameCompacted(minTxnId, maxTxnId);
    }
    return useHive130DeltaDirName() ?
      AcidUtils.deltaSubdir(minTxnId, maxTxnId, 0) : AcidUtils.deltaSubdir(minTxnId, maxTxnId);
  }
in Hive 1.3.0 delta file names changed to delta_xxxx_yyyy_zzzz; prior to that
the name was delta_xxxx_yyyy.  We want to run compaction tests such that both formats
are used since new (1.3) code has to be able to read old files.
ql/src/test/org/apache/hadoop/hive/ql/txn/compactor/CompactorTest.java