Set default picture on image asset and texture nodes.

tests/common_test_class.py

@@ -106,7 +106,8 @@ class AbstractPillarTest(TestMinimal):
 
             return found['_id'], found
 
-    def create_user(self, user_id='cafef00dc379cf10c4aaceaf', roles=('subscriber',)):
+    def create_user(self, user_id='cafef00dc379cf10c4aaceaf', roles=('subscriber',),
+                    groups=None):
         from application.utils.authentication import make_unique_username
 
         with self.app.test_request_context():
@@ -118,7 +119,7 @@ class AbstractPillarTest(TestMinimal):
                 '_updated': datetime.datetime(2016, 4, 15, 13, 15, 11, tzinfo=tz_util.utc),
                 '_created': datetime.datetime(2016, 4, 15, 13, 15, 11, tzinfo=tz_util.utc),
                 'username': make_unique_username('tester'),
-                'groups': [],
+                'groups': groups or [],
                 'roles': list(roles),
                 'settings': {'email_communications': 1},
                 'auth': [{'token': '',