[IMP] stock: default responsible + activity responsible

Traceback when the responsible is not set on an activity
since it's a required field. In this case we will use the
odoo system responsible for the activity.

Also reintroduce the default value for the responsible as
the user that create the product. The purpose is to avoid
to log all the activity for the odoo system but to dispatch
the exception between user, if a user create the product he
will probably be responsible for it. It is always possible
to remove the responsible or to modify it.

Task ID - 1913168

closes odoo/odoo#29138

addons/stock/models/product.py

@@ -396,7 +396,7 @@ class ProductTemplate(models.Model):
     _inherit = 'product.template'
 
     responsible_id = fields.Many2one(
-        'res.users', string='Responsible',
+        'res.users', string='Responsible', default=lambda self: self.env.uid,
         help="This user will be responsible of the next activities related to logistic operations for this product.")
     type = fields.Selection(selection_add=[('product', 'Storable Product')])
     property_stock_production = fields.Many2one(

addons/stock/models/stock_picking.py

@@ -6,7 +6,7 @@ import json
 import time
 
 from itertools import groupby
-from odoo import api, fields, models, _
+from odoo import api, fields, models, SUPERUSER_ID, _
 from odoo.tools import DEFAULT_SERVER_DATETIME_FORMAT
 from odoo.tools.float_utils import float_compare, float_is_zero, float_round
 from odoo.exceptions import UserError
@@ -943,7 +943,7 @@ class Picking(models.Model):
             self.env['mail.activity'].create({
                 'activity_type_id': self.env.ref('mail.mail_activity_data_warning').id,
                 'note': note,
-                'user_id': responsible.id,
+                'user_id': responsible.id or SUPERUSER_ID,
                 'res_id': parent.id,
                 'res_model_id': self.env['ir.model'].search([('model', '=', parent._name)], limit=1).id,
             })