'Test domain-group role assignment maintains existing token.
Test Plan:
- Get a token for user1, scoped to ProjectA
- Create a grant for group1 on DomainB
- Check token is still longer valid'

def test_domain_group_role_assignment_maintains_token(self):

    auth_data = self.build_authentication_request(user_id=self.user1['id'], password=self.user1['password'], project_id=self.projectA['id'])
    token = self.get_requested_token(auth_data)
    self.head('/auth/tokens', headers={'X-Subject-Token': token}, expected_status=http_client.OK)
    grant_url = ('/domains/%(domain_id)s/groups/%(group_id)s/roles/%(role_id)s' % {'domain_id': self.domainB['id'], 'group_id': self.group1['id'], 'role_id': self.role1['id']})
    self.put(grant_url)
    self.head('/auth/tokens', headers={'X-Subject-Token': token}, expected_status=http_client.OK)
