Code review comment for lp:~tribaal/charms/trusty/nova-compute/enable-api-rate-limiting

nova-compute install hook fails on ./tests/014-basic-precise-icehouse amulet test.

0 upgraded, 0 newly installed, 0 to remove and 19 not upgraded.
Traceback (most recent call last):
  File "/var/lib/juju/agents/unit-nova-compute-0/charm/hooks/install.real", line 434, in <module>
    main()
  File "/var/lib/juju/agents/unit-nova-compute-0/charm/hooks/install.real", line 428, in main
    hooks.execute(sys.argv)
  File "/var/lib/juju/agents/unit-nova-compute-0/charm/hooks/charmhelpers/core/hookenv.py", line 672, in execute
    self._hooks[hook_name]()
  File "/var/lib/juju/agents/unit-nova-compute-0/charm/hooks/charmhelpers/contrib/openstack/utils.py", line 777, in wrapped_f
    set_os_workload_status(configs, required_interfaces, charm_func)
  File "/var/lib/juju/agents/unit-nova-compute-0/charm/hooks/charmhelpers/contrib/openstack/utils.py", line 790, in set_os_workload_status
    incomplete_rel_data = incomplete_relation_data(configs, required_interfaces)
  File "/var/lib/juju/agents/unit-nova-compute-0/charm/hooks/charmhelpers/contrib/openstack/utils.py", line 920, in incomplete_relation_data
    complete_ctxts = configs.complete_contexts()
  File "/var/lib/juju/agents/unit-nova-compute-0/charm/hooks/charmhelpers/contrib/openstack/templating.py", line 295, in complete_contexts
    for i in six.itervalues(self.templates)]
  File "/var/lib/juju/agents/unit-nova-compute-0/charm/hooks/charmhelpers/contrib/openstack/templating.py", line 120, in complete_contexts
    self.context()
  File "/var/lib/juju/agents/unit-nova-compute-0/charm/hooks/charmhelpers/contrib/openstack/templating.py", line 107, in context
    ctxt.update(_ctxt)
TypeError: 'APIRateLimitingContext' object is not iterable