@Override
        public void call(RegionObserver observer) throws IOException {
          observer.preScannerClose(this, s);
        }
Supports Coprocessor 'bypass'.
@param s the scanner
@return true if default behavior should be bypassed, false otherwise
@exception IOException Exception
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/RegionCoprocessorHost.java