Improve consistency of the way to look up resource value between SaleOrderLine_getQuantityUnitItemList
and Delivery_updateFastInputLineList.
Because this script is used in two different Fast input (Add Lines and Update Lines), some additional checkings are required.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@40837 20353a03-c40f-0410-a6d1-a30d3c3de9de