[FIX] website_sale: portal users special pricelists is always available

This revision reverts e5b9f02f7a

The argument `website_pl` must always be the default website
pricelist (the public user pricelist), as stated in this
method documentation:

```
:param int website_pl: The default pricelist used on this website
```

So the difference between the public user pricelist
and a specific user pricelist can be made.

A special pricelist set for a specific customer must
always be amongs the available pricelists.

opw-666620

addons/website_sale/models/sale_order.py

@@ -199,9 +199,8 @@ class website(orm.Model):
         :returns: pricelist recordset
         """
         isocountry = request.session.geoip and request.session.geoip.get('country_code') or False
-        user_id = self.pool['res.users'].browse(cr, uid, request.uid or uid, context=context)
         pl_ids = self._get_pl(cr, uid, isocountry, show_visible,
-                              user_id.partner_id.property_product_pricelist.id,
+                              request.website.user_id.sudo().partner_id.property_product_pricelist.id,
                               request.session.get('website_sale_current_pl'),
                               request.website.website_pricelist_ids)
         return self.pool['product.pricelist'].browse(cr, uid, pl_ids, context=context)