void regionClosedWithoutPersistingToMeta(RegionStateNode regionNode)
    throws UnexpectedStateException {
    ServerName regionLocation = regionNode.getRegionLocation();
    regionNode.transitionState(State.CLOSED, STATES_EXPECTED_ON_CLOSED);
    regionNode.setRegionLocation(null);
    if (regionLocation != null) {
      regionNode.setLastHost(regionLocation);
      regionStates.removeRegionFromServer(regionLocation, regionNode);
    }
  }
Resolve a cached {@link RegionInfo} from the encoded region name as a {@code String}.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/AssignmentManager.java