@Override
  protected boolean isRollbackSupported(final RegionTransitionState state) {
    switch (state) {
      case REGION_TRANSITION_QUEUE:
        return true;
      default:
        return false;
    }
  }
Leave here only for checking if we can successfully start the master.
@deprecated Do not use any more.
@see TransitRegionStateProcedure
hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/AssignProcedure.java