@Override
  public boolean cleanupTestDir() {
    boolean ret = super.cleanupTestDir();
    if (deleteDir(this.clusterTestDir)) {
      this.clusterTestDir = null;
      return ret;
    }
    return false;
  }
Returns True if we removed the test dirs
hbase-testing-util/src/main/java/org/apache/hadoop/hbase/HBaseZKTestingUtility.java