Define its own _baseGetTypeClass to avoid a bootstrap issue.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@39424 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Type/ERP5Type.py

@@ -423,6 +423,10 @@ class ERP5TypeInformation(XMLObject,
       """Getter for 'type_base_category' property"""
       return list(self.base_category_list)
 
+    # XXX this is required for a bootstrap issue.
+    def _baseGetTypeClass(self):
+      return getattr(aq_base(self), 'type_class', None)
+
     security.declareProtected(Permissions.AccessContentsInformation,
                               'getTypeClass')
     def getTypeClass(self):