Comment 15 for bug 1655182

I have verified this fix using the steps detailed in the test case and can confirm that the fix is good:

root@juju-58b2b9-default-7:~# keystone-manage mapping_engine --rules mapping.json --input input.txt
{
  "group_ids": [],
  "user": {
    "domain": {
      "id": "default"
    },
    "type": "local",
    "name": "abc"
  },
  "group_names": []
}