ignore non-available PropertySheet in createAllPropertySheetsFromFilesystem().

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@43279 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Type/Tool/PropertySheetTool.py

@@ -73,6 +73,8 @@ class PropertySheetTool(BaseTool):
     for name, klass in PropertySheet.__dict__.iteritems():
       if name[0] == '_':
         continue
+      elif isinstance(klass, str): # Property Sheet is not available
+        continue
 
       if name in self.objectIds():
         if erase_existing: