[FIX] website_sale: Avoid map tax for every company

When a product has multiple company taxes and b2c prices is enabled, price is
not computed properly and adds to the base price every company tax present.
This patch filters the company set on the company so taxes are computed just
for that company.

This commit closes #18840

Depend of the previous commit which add right to public user. #18881

addons/website_sale/models/product.py

@@ -183,7 +183,9 @@ class Product(models.Model):
     def _website_price(self):
         qty = self._context.get('quantity', 1.0)
         partner = self.env.user.partner_id
-        pricelist = self.env['website'].get_current_website().get_current_pricelist()
+        current_website = self.env['website'].get_current_website()
+        pricelist = current_website.get_current_pricelist()
+        company_id = current_website.company_id
 
         context = dict(self._context, pricelist=pricelist.id, partner=partner)
         self2 = self.with_context(context) if self._context != context else self
@@ -191,7 +193,7 @@ class Product(models.Model):
         ret = self.env.user.has_group('sale.group_show_price_subtotal') and 'total_excluded' or 'total_included'
 
         for p, p2 in pycompat.izip(self, self2):
-            taxes = partner.property_account_position_id.map_tax(p.taxes_id)
+            taxes = partner.property_account_position_id.map_tax(p.taxes_id.filtered(lambda x: x.company_id == company_id))
             p.website_price = taxes.compute_all(p2.price, pricelist.currency_id, quantity=qty, product=p2, partner=partner)[ret]
             p.website_public_price = taxes.compute_all(p2.lst_price, quantity=qty, product=p2, partner=partner)[ret]
 
@@ -200,6 +202,7 @@ class Product(models.Model):
         self.ensure_one()
         return self.product_tmpl_id.website_publish_button()
 
+
 class ProductAttribute(models.Model):
     _inherit = "product.attribute"