[FIX] point_of_sale: change check for tips default value

Current behavior:
If you delete the default tip product, then activate tips in the PoS
config you will be blocked by a warning message saying that the tip
product is not set even if you set it. To fix this we only check if the
tip product exist if the tips are activated for the current config.
We also remove the compute on the tip product field so that we can set
any product as a tip product.

Steps to reproduce:
-Delete Tip Product
-Open PoS config
-Activate tips
-Try to save, you will be blocked by a warning message
-If you try to turn off the tips, you will be blocked by the same
 warning message

opw-3519123

closes odoo/odoo#138109

X-original-commit: 715dd599baa4fec124c7ec84fee11df0550251b8
Signed-off-by: Vlad Stroia (vlst) <vlst@odoo.com>
Signed-off-by: Robin Engels (roen) <roen@odoo.com>

addons/point_of_sale/models/pos_config.py

@@ -55,6 +55,12 @@ class PosConfig(models.Model):
     def _get_group_pos_user(self):
         return self.env.ref('point_of_sale.group_pos_user')
 
+    def _get_default_tip_product(self):
+        tip_product_id = self.env.ref("point_of_sale.product_product_tip", raise_if_not_found=False)
+        if not tip_product_id:
+            tip_product_id = self.env['product.product'].search([('default_code', '=', 'TIPS')], limit=1)
+        return tip_product_id
+
     name = fields.Char(string='Point of Sale', required=True, help="An internal identification of the point of sale.")
     printer_ids = fields.Many2many('pos.printer', 'pos_config_printer_rel', 'config_id', 'printer_id', string='Order Printers')
     is_order_printer = fields.Boolean('Order Printer')
@@ -137,8 +143,7 @@ class PosConfig(models.Model):
     group_pos_user_id = fields.Many2one('res.groups', string='Point of Sale User Group', default=_get_group_pos_user,
         help='This field is there to pass the id of the pos user group to the point of sale client.')
     iface_tipproduct = fields.Boolean(string="Product tips")
-    tip_product_id = fields.Many2one('product.product', string='Tip Product', compute='_compute_tip_product_id', store=True,
-        help="This product is used as reference on customer receipts.")
+    tip_product_id = fields.Many2one('product.product', string='Tip Product', default=_get_default_tip_product, help="This product is used as reference on customer receipts.")
     fiscal_position_ids = fields.Many2many('account.fiscal.position', string='Fiscal Positions', help='This is useful for restaurants with onsite and take-away services that imply specific tax rates.')
     default_fiscal_position_id = fields.Many2one('account.fiscal.position', string='Default Fiscal Position')
     default_bill_ids = fields.Many2many('pos.bill', string="Coins/Bills")
@@ -254,13 +259,6 @@ class PosConfig(models.Model):
         for config in self:
             config.iface_customer_facing_display = config.iface_customer_facing_display_via_proxy or config.iface_customer_facing_display_local
 
-    @api.depends('iface_tipproduct')
-    def _compute_tip_product_id(self):
-        for pos_config in self:
-            pos_config.tip_product_id = self.env.ref("point_of_sale.product_product_tip", raise_if_not_found=False)
-            if not pos_config.tip_product_id:
-                pos_config.tip_product_id = self.env['product.product'].search([('default_code', '=', 'TIPS')], limit=1)
-
     @api.depends('iface_customer_facing_display')
     def _compute_iface_customer_facing_display_background_image_1920(self):
         for config in self:
@@ -394,7 +392,7 @@ class PosConfig(models.Model):
         return pos_configs
 
     def _reset_default_on_vals(self, vals):
-        if 'tip_product_id' in vals and any(self.mapped('iface_tipproduct')) and not vals['tip_product_id']:
+        if 'tip_product_id' in vals and vals['iface_tipproduct'] and not vals['tip_product_id']:
             default_product = self.env.ref('point_of_sale.product_product_tip', False)
             if default_product:
                 vals['tip_product_id'] = default_product.id