default void postCompactSelection(ObserverContext<? extends RegionCoprocessorEnvironment> c,
    Store store, List<? extends StoreFile> selected, CompactionLifeCycleTracker tracker,
    CompactionRequest request) {
  }
Called after the {@link StoreFile}s to compact have been selected from the available
candidates.
@param c        the environment provided by the region server
@param store    the store being compacted
@param selected the store files selected to compact
@param tracker  tracker used to track the life cycle of a compaction
@param request  the requested compaction
hbase-server/src/main/java/org/apache/hadoop/hbase/coprocessor/RegionObserver.java