Fix issue with V3 Authentication.

Unscoped token does not have a roles attribute in it. Fix the
code to handle non-existent of roles in the Auth Token.

Fixes: bug #1202385

Change-Id: I2bd101e3ed2dd37da86f84773c2b9dafc0717d3b

openstack_auth/tests/data_v3.py

@@ -213,7 +213,6 @@ def generate_test_data():
                     'name': domain_dict['name']
                 }
             },
-            'roles': [role_dict],
             'catalog': [keystone_service]
         }
     }

openstack_auth/user.py

@@ -77,9 +77,9 @@ class Token(object):
         self.domain = domain
 
         if auth_ref.version == 'v2.0':
-            self.roles = auth_ref['user']['roles']
+            self.roles = auth_ref['user'].get('roles', [])
         else:
-            self.roles = auth_ref['roles']
+            self.roles = auth_ref.get('roles', [])
 
         if get_keystone_version() < 3:
             self.serviceCatalog = auth_ref.get('serviceCatalog', [])