Description of problem:
running test tempest.api.identity.admin.v3.test_trusts.TrustsV3TestJSON.test_get_trusts_all fails with authorization denied.

Version-Release number of selected component (if applicable):
openstack-tempest-liberty-20160317.1.el7ost.noarch

How reproducible:
every time.

Steps to Reproduce:
1. source a v3-enabled rc file
2. run tools/run-tests.sh tempest.api.identity.admin.v3.test_trusts.TrustsV3TestJSON.test_get_trusts_all
3.

Actual results:
Fails but with an auth denied error:
    2016-07-27 08:11:15,576 23926 INFO     [tempest.lib.common.rest_client] Request (TrustsV3TestJSON:setUp): 401 GET http://172.31.10.96:5000/v3/users 0.040s
    2016-07-27 08:11:15,577 23926 DEBUG    [tempest.lib.common.rest_client] Request - Headers: {'Content-Type': 'application/json', 'Accept': 'application/json', 'X-Auth-Token': '<omitted>'}
            Body: None
        Response - Headers: {'status': '401', 'content-length': '114', 'vary': 'X-Auth-Token', 'www-authenticate': 'Keystone uri="https://clvcw1ov201.uae-dev.cmn-model.corp.telstra.com:13000"', 'connection': 'close', 'date': 'Wed, 27 Jul 2016 12:11:28 GMT', 'content-type': 'application/json', 'x-openstack-request-id': 'req-ce36422f-8099-4e0f-afe3-90f88b1d7fbb'}
            Body: {"error": {"message": "The request you have made requires authentication.", "code": 401, "title": "Unauthorized"}}

Expected results:
Pass (or fail) but based on the test, not access to it.

Additional info:

Keystone logs show
2016-07-27 21:08:48.685 6330 WARNING keystone.common.wsgi [req-b8ba511e-102f-4347-8a08-25566f4b446e - - - - -] Authorization failed. The request you have made requires authentication. from 172.31.10.68
when runnnig the test.