Fix erp5_xhtml_style.breadcrumbs migration regarding portal_properties

erp5_xhtml_style.breadcrumbs tries to access portal_properties, which
does not exist anymore (see commit
8721c675dae39611de884a9e6d6301978954c8c5, in which CMFDefault was
dropped).

The migration code here allows access to the ERP5 interface, which would
be completely broken otherwise.

product/ERP5Type/dynamic/portal_type_class.py

@@ -470,6 +470,9 @@ def synchronizeDynamicModules(context, force=False):
           if portal.hasObject(tool_id):
             portal._delObject(tool_id, suppress_events=True)
             migrate = True
+            if tool_id == 'portal_properties':
+              portal.portal_skins.erp5_xhtml_style.breadcrumbs.write(
+                'return []')
 
         if migrate:
           portal.migrateToPortalTypeClass()