test_asg_scale_up_max_size fails with KeyError

Fails with the below trace:

2017-01-04 12:00:05.478362 | 2017-01-04 12:00:05.476 | Traceback (most recent call last):
2017-01-04 12:00:05.479994 | 2017-01-04 12:00:05.479 | File "/opt/stack/new/heat/heat_integrationtests/functional/test_heat_autoscaling.py", line 120, in test_asg_scale_up_max_size
2017-01-04 12:00:05.482205 | 2017-01-04 12:00:05.481 | asg.physical_resource_id, expected_resources)
2017-01-04 12:00:05.484362 | 2017-01-04 12:00:05.483 | File "/opt/stack/new/heat/heat_integrationtests/common/test.py", line 54, in call_until_true
2017-01-04 12:00:05.486063 | 2017-01-04 12:00:05.485 | if func(*args, **kwargs):
2017-01-04 12:00:05.488806 | 2017-01-04 12:00:05.488 | File "/opt/stack/new/heat/heat_integrationtests/common/test.py", line 649, in check_autoscale_complete
2017-01-04 12:00:05.491046 | 2017-01-04 12:00:05.490 | res_list = self.client.resources.list(stack_id)
2017-01-04 12:00:05.493215 | 2017-01-04 12:00:05.492 | File "/usr/local/lib/python2.7/dist-packages/heatclient/v1/resources.py", line 71, in list
2017-01-04 12:00:05.495393 | 2017-01-04 12:00:05.494 | return self._list(url, "resources")
2017-01-04 12:00:05.497396 | 2017-01-04 12:00:05.496 | File "/usr/local/lib/python2.7/dist-packages/heatclient/common/base.py", line 118, in _list
2017-01-04 12:00:05.499280 | 2017-01-04 12:00:05.498 | body = self.client.get(url).json()
2017-01-04 12:00:05.501352 | 2017-01-04 12:00:05.500 | File "/usr/local/lib/python2.7/dist-packages/heatclient/common/http.py", line 287, in get
2017-01-04 12:00:05.503475 | 2017-01-04 12:00:05.502 | return self.client_request("GET", url, **kwargs)
2017-01-04 12:00:05.505546 | 2017-01-04 12:00:05.504 | File "/usr/local/lib/python2.7/dist-packages/heatclient/common/http.py", line 280, in client_request
2017-01-04 12:00:05.507506 | 2017-01-04 12:00:05.507 | resp, body = self.json_request(method, url, **kwargs)
2017-01-04 12:00:05.509742 | 2017-01-04 12:00:05.509 | File "/usr/local/lib/python2.7/dist-packages/heatclient/common/http.py", line 269, in json_request
2017-01-04 12:00:05.511695 | 2017-01-04 12:00:05.511 | resp = self._http_request(url, method, **kwargs)
2017-01-04 12:00:05.513828 | 2017-01-04 12:00:05.513 | File "/usr/local/lib/python2.7/dist-packages/heatclient/common/http.py", line 241, in _http_request
2017-01-04 12:00:05.515766 | 2017-01-04 12:00:05.515 | resp = self._http_request(location, method, **kwargs)
2017-01-04 12:00:05.517712 | 2017-01-04 12:00:05.517 | File "/usr/local/lib/python2.7/dist-packages/heatclient/common/http.py", line 232, in _http_request
2017-01-04 12:00:05.519488 | 2017-01-04 12:00:05.519 | raise exc.from_response(resp)
2017-01-04 12:00:05.521586 | 2017-01-04 12:00:05.521 | heatclient.exc.HTTPInternalServerError: ERROR: u'u\'775lfnyg63f4\'\n

Engine Log.

http://logs.openstack.org/60/415160/3/check/gate-heat-dsvm-functional-orig-mysql-lbaasv2-ubuntu-xenial/95f5b19/logs/screen-h-eng.txt.gz?level=TRACE#_2017-01-04_11_51_33_181