@Override
  public Entry filter(Entry entry) {
    // Do not filter out an entire entry by replication scopes. As now we support serial
    // replication, the sequence id of a marker is also needed by upper layer. We will filter out
    // all the cells in the filterCell method below if the replication scopes is null or empty.
    return entry;
  }
Keeps KVs that are scoped other than local
hbase-server/src/main/java/org/apache/hadoop/hbase/replication/ScopeWALEntryFilter.java