Split failure may cause region hole and data loss when use zk assign

public PairOfSameType<Region> execute(final Server server,
      final RegionServerServices services, User user) throws IOException {
    this.server = server;
    this.rsServices = services;
    useZKForAssignment = server == null ? true :
      ConfigUtil.useZKForAssignment(server.getConfiguration());
    if (useCoordinatedStateManager(server)) {
      std =
          ((BaseCoordinatedStateManager) server.getCoordinatedStateManager())
              .getSplitTransactionCoordination().getDefaultDetails();
    }
    PairOfSameType<Region> regions = createDaughters(server, services, user);
    if (this.parent.getCoprocessorHost() != null) {
      if (user == null) {
        parent.getCoprocessorHost().preSplitAfterPONR();
      } else {
        try {
          user.getUGI().doAs(new PrivilegedExceptionAction<Void>() {
            @Override
            public Void run() throws Exception {
              parent.getCoprocessorHost().preSplitAfterPONR();
              return null;
            }
          });
        } catch (InterruptedException ie) {
          InterruptedIOException iioe = new InterruptedIOException();
          iioe.initCause(ie);
          throw iioe;
        }
      }
    }
    
    //sleep here!!!
    try {
      Thread.sleep(1000 * 60 * 60);
    } catch (InterruptedException e) {
      e.printStackTrace();
    }

    regions = stepsAfterPONR(server, services, regions, user);

    transition(SplitTransactionPhase.COMPLETED);

    return regions;
  }