[FIX] sale_coupon(_delivery): correct discount when specific product

Before this commit:
1. With a coupon set on 'specific_product', the discount amount was multiplied
   by the product quantity twice.
   (Introduced by a42c27f which apply discount on the full price by using
   price_total (already multiplied by quantity) over price_unit.
2. With a coupon set on 'cheapest_product', the discount was not discounting taxes.
3. With a coupon set on 'cheapest_product' and `sale_coupon_delivery` installed, it
   would simply crashes and throws an error since `sale.order.line` has no
   `program_id` attribute.

Now:
1. We no longer multiply by the quantity twice;
2. We apply discount on the full price (with taxes);
3. We use correct attribute to avoid crash.

opw-1830986

0 files changed, 0 insertions, 0 deletions