Assume None as 0.0 in _getTargetTotalPrice.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@1998 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5/Document/DeliveryLine.py

@@ -211,7 +211,9 @@ Une ligne tarifaire."""
 
     def _getTargetTotalPrice(self, context):
       if not self.hasCellContent():
-        return self.getTargetQuantity() * self.getPrice(context=context)
+        target_quantity = self.getTargetQuantity() or 0.0
+        price = self.getPrice(context=context) or 0.0
+        return target_quantity * price
       else:
         # Use MySQL
         aggregate = self.DeliveryLine_zGetTotal()[0]