Comment 1 for bug 1485956

It looks like this commit is where the problem was introduced
https://review.openstack.org/#/c/209000/
"Refactor format_resource_attributes"

Here is a tracback I'm seeing that may be relevant (when trying to download the software config data from a overcloud instance)

2015-08-21 13:41:23,912 ERROR Error marking resource as failed
 Traceback (most recent call last):
   File "/opt/stack/venvs/openstack/lib/python2.7/site-packages/heat/engine/resource.py", line 646, in _action_recorder
     self.state_set(action, self.FAILED, '%s aborted' % action)
   File "/opt/stack/venvs/openstack/lib/python2.7/site-packages/heat/engine/resource.py", line 1429, in state_set
     self._store_or_update(action, status, reason)
   File "/opt/stack/venvs/openstack/lib/python2.7/site-packages/heat/engine/resource.py", line 1277, in _store_or_update
     'stack_id': self.stack.id,
   File "/opt/stack/venvs/openstack/lib/python2.7/site-packages/heat/engine/resource.py", line 276, in stack
     assert stack is not None, "Need a reference to the Stack object"
 AssertionError: Need a reference to the Stack object
Aug 21 13:41:24 localhost.localdomain.localdomain sudo[897]: pam_unix(sudo:session): session closed for user root