'GET /users?domain_id=mydomain (filtered).
Test Plan:
- Update policy so api is unprotected
- Use an un-scoped token to make sure we can filter the
users by domainB, getting back the 2 users in that domain'

def test_list_users_filtered_by_domain(self):

    self._set_policy({'identity:list_users': []})
    url_by_name = ('/users?domain_id=%s' % self.domainB['id'])
    r = self.get(url_by_name, auth=self.auth)
    id_list = self._get_id_list_from_ref_list(r.result.get('users'))
    self.assertIn(self.user2['id'], id_list)
    self.assertIn(self.user3['id'], id_list)
