@BeforeClass
  public static void setUpBeforeClass() throws Exception {
    RSGroupUtil.enableRSGroup(TEST_UTIL.getConfiguration());
    TEST_UTIL.startMiniCluster(5);
  }
Test for rsgroup enable, unloaded regions from decommissoned host of a rsgroup should be assigned
to those regionservers belonging to the same rsgroup.
hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestRegionMoverWithRSGroupEnable.java