@Override
  protected WAL createRemoteWAL(RegionInfo region, FileSystem remoteFs, Path remoteWALDir,
    String prefix, String suffix) throws IOException {
    // so we do not need to add this for a lot of test classes, for normal WALProvider, you should
    // implement this method to support sync replication.
    throw new UnsupportedOperationException();
  }
iff the given WALFactory is using the DefaultWALProvider for meta and/or non-meta, count the
size of files (only rolled). if either of them aren't, count 0 for that provider.
hbase-server/src/main/java/org/apache/hadoop/hbase/wal/AbstractFSWALProvider.java