fix a typo.

product/ERP5/Tool/ConversionTool.py

@@ -86,7 +86,7 @@ class ConversionTool(BaseTool):
 
   def filtered_meta_types(self, user=None):
     # Filters the list of available meta types.
-    all = SolverTool.inheritedAttribute('filtered_meta_types')(self)
+    all = BaseTool.inheritedAttribute('filtered_meta_types')(self)
     meta_types = []
     for meta_type in self.all_meta_types():
       if meta_type['name'] in self.allowed_types: