Support add/update/remove/delete on on_change_with for one2many
Since 8e8f1a801098 by documentation we do not support any more that
on_change_with returns a sets of actions.
But practically it is only d142b33fa3ab which break the unintentional backward compatibility (it set on the record the value returned by
This means that only a list of ids can be returned to the client for the
on_change_with on xxx2many.
I think we could improve the situation by reusing the
_changed_values for the on_change_with.