public static List<ExtendedCell> getExtendedCells(WALEdit edit) {
    return edit.getExtendedCells();
  }
A helper class so we can call some package private methods of {@link WALEdit} from other
packages. Since {@link WALEdit} has been exposed to coprocessor and replication implementations,
we do not want to make all the methods in it public.
hbase-server/src/main/java/org/apache/hadoop/hbase/wal/WALEditInternalHelper.java