static void removeNamespacePermissions(Configuration conf, String namespace, Table t)
    throws IOException {
    Delete d = new Delete(Bytes.toBytes(toNamespaceEntry(namespace)));
    d.addFamily(ACL_LIST_FAMILY);
    if (LOG.isDebugEnabled()) {
      LOG.debug("Removing permissions of removed namespace " + namespace);
    }

    try {
      t.delete(d);
    } finally {
      t.close();
    }
  }
Remove specified namespace from the acl table.
hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/PermissionStorage.java