Workflow.py: accept None guard, but only for debugging.

product/ERP5Workflow/Document/Workflow.py

@@ -204,7 +204,9 @@ class Workflow(IdAsReferenceMixin("", "prefix"), XMLObject):
   def _checkTransitionGuard(self, tdef, document, **kw):
     guard = tdef.getGuard()
     if guard is None:
-      return 0
+      # in new workflow transition, guard shouldn't be none any more, this
+      # condiction is only kept for debugging.
+      return 1
     if guard.check(getSecurityManager(), self, document, **kw):
       return 1
     return 0