Workflow.py: check before script type before execution.

product/ERP5Workflow/Document/Workflow.py

@@ -616,8 +616,9 @@ class Workflow(IdAsReferenceMixin("", "prefix"), XMLObject):
       if script_id:
         script = self._getOb(script_id, None)
         # Pass lots of info to the script in a single parameter.
-        kwargs = form_kw
-        sci = StateChangeInfo(
+        if script.getTypeInfo().getId() == 'Workflow Script':
+          kwargs = form_kw
+          sci = StateChangeInfo(
               document, self, former_status, tdef, old_sdef, new_sdef, kwargs)
         try:
           script(sci)  # May throw an exception.