make sure the message list is empty with tic

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@1470 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Type/tests/ERP5TypeTestCase.py

@@ -158,6 +158,7 @@ class ERP5TypeTestCase(PortalTestCase):
       """
       portal_activities = getattr(self.getPortal(),'portal_activities',None)
       if portal_activities is not None:
+        while len(portal_activities.getMessageList()) > 0:
           portal_activities.distribute()
           portal_activities.tic()