default void preFlushScannerOpen(ObserverContext<? extends RegionCoprocessorEnvironment> c,
    Store store, ScanOptions options, FlushLifeCycleTracker tracker) throws IOException {
  }
Called before we open store scanner for flush. You can use the {@code options} to change max
versions and TTL for the scanner being opened.
@param c       the environment provided by the region server
@param store   the store where flush is being requested
@param options used to change max versions and TTL for the scanner being opened
hbase-server/src/main/java/org/apache/hadoop/hbase/coprocessor/RegionObserver.java