@Override
  protected boolean isNewKey(ExtendedCell cell) {
    if (this.getLastCell() != null) {
      return !CellUtil.matchingRows(cell, this.getLastCell());
    }
    return true;
  }
Handles ROW bloom related context. It works with both ByteBufferedCell and byte[] backed cells
hbase-server/src/main/java/org/apache/hadoop/hbase/util/RowBloomContext.java