Reuse Movement_isQuantityEditable to know if this fast input must update quantities on movement or not.
Remove XXX, the case where the variation is not in range will not happen, because the list method will only allow to select matching variations

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@27191 20353a03-c40f-0410-a6d1-a30d3c3de9de