Worklist.py: when generating guard, create an empty guard first.

product/ERP5Workflow/Document/Worklist.py

@@ -87,10 +87,7 @@ class Worklist(IdAsReferenceMixin("worklist_", "prefix"), XMLObject):
 
     def generateGuard(self):
         if self.guard == None:
-          self.guard = Guard(permissions=self.getPermissionList(),
-                        roles=self.getRoleList(),
-                        groups=self.getGroupList(),
-                        expr=Expression(self.getExpression()))
+          self.guard = Guard()
         if self.getRoleList() is not None:
           self.guard.roles = self.getRoleList()
         if self.getPermissionList() is not None:
@@ -170,7 +167,7 @@ class Worklist(IdAsReferenceMixin("worklist_", "prefix"), XMLObject):
         LOG(" ***** props in worklist is '%s'"%props, 0, 0)
         for k in props:
           # in new worklist, use properties to set value.
-          v = props.get(k)
+          v = props.get(k, '')
           if v:
             if k == 'guard_expr':
               self.setExpression(v)