db_api.user_creds_get() traceback during tests

[Jason Dunsmore]

I see the following traceback occasionally during a tox run (the tests still pass):

Traceback (most recent call last):
  File "/home/jason/github/heat/.tox/py27/local/lib/python2.7/site-packages/eventlet/hubs/hub.py", line 346, in fire_timers
    timer()
  File "/home/jason/github/heat/.tox/py27/local/lib/python2.7/site-packages/eventlet/hubs/timer.py", line 56, in __call__
    cb(*args, **kw)
  File "/home/jason/github/heat/.tox/py27/local/lib/python2.7/site-packages/eventlet/greenthread.py", line 194, in main
    result = function(*args, **kwargs)
  File "heat/engine/parser.py", line 625, in delete
    user_creds = db_api.user_creds_get(stack.user_creds_id)
AttributeError: 'NoneType' object has no attribute 'user_creds_id'

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/72702

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/72702
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=ed7710cd3b97c6a04e513d972870d2e341ea32c3
Submitter: Jenkins
Branch: master

commit ed7710cd3b97c6a04e513d972870d2e341ea32c3
Author: Thomas Herve <email address hidden>
Date: Tue Feb 11 17:50:13 2014 +0100

    Remove spurious tracebacks from tests

    Some tests were deleting stacks in the background, thus provoking
    tracebacks displayed later on during tests run. The patch waits for the
    delete threads to prevent that.

    Closes-Bug: #1278836
    Closes-Bug: #1278937
    Change-Id: I4b90eb6f90168803445039f9588a3052def6636a