default void postClose(ObserverContext<? extends RegionCoprocessorEnvironment> c,
    boolean abortRequested) {
  }
Called after the region is reported as closed to the master.
@param c              the environment provided by the region server
@param abortRequested true if the region server is aborting
hbase-server/src/main/java/org/apache/hadoop/hbase/coprocessor/RegionObserver.java