Fix missing variable initialization

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk/utils@45922 20353a03-c40f-0410-a6d1-a30d3c3de9de

erp5/util/benchmark/performance_tester.py

@@ -176,6 +176,8 @@ class PerformanceTester(object):
 
           i = 0
           continue
+        else:
+          msg = None
 
       if msg is not None:
         error_message_set.add(msg)