private Map<String, Permission> prepareCellPermissions(String[] users, Action... action) {
    Map<String, Permission> perms = new HashMap<>(2);
    for (String user : users) {
      perms.put(user, new Permission(action));
    }
    return perms;
  }
Insure we are not granting access in the absence of any cells found when scanning for covered
cells.
hbase-server/src/test/java/org/apache/hadoop/hbase/security/access/TestCellACLs.java