@Override
  protected CellFlatMap<T> createSubCellFlatMap(int min, int max, boolean descending) {
    return new CellChunkMap<>(this.comparator(), this.chunks, min, max, descending);
  }
To be used by base (CellFlatMap) class only to create a sub-CellFlatMap Should be used only to
create only CellChunkMap from CellChunkMap
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/CellChunkMap.java