[FIX] website: res_config_setting in multi company

Before this commit, if the first website in the select was not in your current
company, it raises a traceback.

Now with filter on your own company, and support empty website selected
removing required on related field and using attrs dynamic to make it required

closes odoo/odoo#30769

addons/website/models/res_config_settings.py

@@ -4,14 +4,13 @@
 from ast import literal_eval
 
 from odoo import api, fields, models
-from odoo.exceptions import AccessDenied
 
 
 class ResConfigSettings(models.TransientModel):
     _inherit = 'res.config.settings'
 
     def _default_website(self):
-        return self.env['website'].search([], limit=1)
+        return self.env['website'].search([('company_id', '=', self.env.user.company_id.id)], limit=1)
 
     website_id = fields.Many2one('website', string="website",
                                  default=_default_website, ondelete='cascade')
@@ -23,7 +22,7 @@ class ResConfigSettings(models.TransientModel):
     language_count = fields.Integer(string='Number of languages', compute='_compute_language_count', readonly=True)
     website_default_lang_id = fields.Many2one(
         string='Default language', related='website_id.default_lang_id', readonly=False,
-        relation='res.lang', required=True,
+        relation='res.lang', required=False,
         oldname='default_lang_id')
     website_default_lang_code = fields.Char(
         'Default language code', related='website_id.default_lang_code', readonly=False,

addons/website/views/res_config_settings_views.xml

@@ -17,7 +17,7 @@
                                         Settings on this page will apply to this website
                                     </div>
                                     <div class="mt16">
-                                        <field name="website_id" widget="selection" required="1"/>
+                                        <field name="website_id" widget="selection"/>
                                     </div>
                                     <div>
                                         <button name="action_website_create_new" type="object" string="Create a New Website" class="btn-secondary" icon="fa-arrow-right"/>
@@ -41,7 +41,7 @@
                                     <div class="content-group">
                                         <div class="row mt16">
                                             <label class="col-lg-3 o_light_label" string="Name" for="website_name"/>
-                                            <field name="website_name" required="1"/>
+                                            <field name="website_name" attrs="{'required': [('website_id', '!=', False)] }"/>
                                         </div>
                                         <div class="row">
                                             <label class="col-lg-3 o_light_label" for="favicon" />
@@ -74,7 +74,7 @@
                                         <field name="language_count" invisible="1"/>
                                         <div class="mt8" attrs="{'invisible':[('language_count', '&lt;', 2)]}">
                                             <label class="o_light_label mr8" string="Default" for="website_default_lang_id"/>
-                                            <field name="website_default_lang_id" widget="selection"/>
+                                            <field name="website_default_lang_id" widget="selection" attrs="{'required': [('website_id', '!=', False)]}"/>
                                         </div>
                                     </div>
                                     <div>