[REF] mail: cleanup context usage in composer

Purpose of this commit is to cleanup context usage in composer

  * remove now dead 'custom_layout' context keys that was present mainly for
    compatibility until Odoo v15. You should now correctly use default value
    for 'email_layout_xmlid' field like every field;
  * remove 'mail_auto_delete' context key, not used anywhere in codebase.
    Auto-delete field of composer will be improved soon so that setting it
    as every field will replace the context usage;
  * remove usage of self._context, to use self.env.context;

Task-2710804 (Mail: Clean MailThread Posting API)

Part-of: odoo/odoo#99482

addons/mail/wizard/mail_compose_message.py

@@ -50,10 +50,6 @@ class MailComposer(models.TransientModel):
                 - active_ids: record IDs
                 - default_model or active_model
         """
-        # backward compatibility of context before addition of
-        # email_layout_xmlid field: to remove in 15.1+
-        if self._context.get('custom_layout') and 'default_email_layout_xmlid' not in self._context:
-            self = self.with_context(default_email_layout_xmlid=self._context['custom_layout'])
         # support subtype xmlid, like ``message_post``, when easier than using ``ref``
         if self.env.context.get('default_subtype_xmlid'):
             self = self.with_context(
@@ -75,16 +71,16 @@ class MailComposer(models.TransientModel):
                 result['author_id'] = author_id
 
         if 'model' in fields and 'model' not in result:
-            result['model'] = self._context.get('active_model')
+            result['model'] = self.env.context.get('active_model')
         if 'res_id' in fields and 'res_id' not in result:
-            result['res_id'] = self._context.get('active_id')
+            result['res_id'] = self.env.context.get('active_id')
         if 'reply_to_mode' in fields and 'reply_to_mode' not in result and result.get('model'):
             # doesn't support threading
             if result['model'] not in self.env or not hasattr(self.env[result['model']], 'message_post'):
                 result['reply_to_mode'] = 'new'
 
-        if 'active_domain' in self._context:  # not context.get() because we want to keep global [] domains
-            result['active_domain'] = '%s' % self._context.get('active_domain')
+        if 'active_domain' in self.env.context:  # not context.get() because we want to keep global [] domains
+            result['active_domain'] = '%r' % self.env.context.get('active_domain')
         if result.get('composition_mode') == 'comment' and (set(fields) & set(['model', 'res_id', 'partner_ids', 'record_name', 'subject'])):
             result.update(self.get_record_data(result))
 
@@ -367,8 +363,8 @@ class MailComposer(models.TransientModel):
             # wizard works in batch mode: [res_id] or active_ids or active_domain
             if mass_mode and wizard.use_active_domain and wizard.model:
                 res_ids = self.env[wizard.model].search(ast.literal_eval(wizard.active_domain)).ids
-            elif mass_mode and wizard.model and self._context.get('active_ids'):
-                res_ids = self._context['active_ids']
+            elif mass_mode and wizard.model and self.env.context.get('active_ids'):
+                res_ids = self.env.context['active_ids']
             else:
                 res_ids = [wizard.res_id]
 
@@ -460,7 +456,7 @@ class MailComposer(models.TransientModel):
             # generate the saved template
             record.write({'template_id': template.id})
             record._onchange_template_id_wrapper()
-            return _reopen(self, record.id, record.model, context=self._context)
+            return _reopen(self, record.id, record.model, context=self.env.context)
 
     # ------------------------------------------------------------
     # RENDERING / VALUES GENERATION
@@ -580,7 +576,7 @@ class MailComposer(models.TransientModel):
             values.update(
                 email_add_signature=not bool(self.template_id) and self.email_add_signature,
                 email_layout_xmlid=self.email_layout_xmlid,
-                mail_auto_delete=self.template_id.auto_delete if self.template_id else self.env.context.get('mail_auto_delete', True),
+                mail_auto_delete=self.template_id.auto_delete if self.template_id else True,
                 model_description=model_description,
             )
         return values

addons/test_mail/tests/test_mail_composer.py

@@ -1056,26 +1056,6 @@ class TestComposerResultsComment(TestMailComposer):
         self.assertEqual(len(self._new_mails), 2, 'Should have created 2 mail.mail (1 for users, 1 for customers)')
         self.assertEqual(len(self._new_mails.exists()), 0, 'To fix: does not respect auto_delete')
 
-        # ensure ``mail_auto_delete`` context key allow to override this behavior
-        composer = self.env['mail.compose.message'].with_context(
-            self._get_web_context(self.test_record),
-            mail_auto_delete=False,
-        ).create({
-            'body': '<p>Test Body</p>',
-            'partner_ids': [(4, self.partner_1.id), (4, self.partner_2.id)]
-        })
-        with self.mock_mail_gateway(mail_unlink_sent=True):
-            composer._action_send_mail()
-
-        # notifications
-        message = self.test_record.message_ids[0]
-        self.assertEqual(message.notified_partner_ids, self.partner_employee_2 + self.partner_1 + self.partner_2)
-
-        # global outgoing
-        self.assertEqual(len(self._mails), 3, 'Should have sent an email each recipient')
-        self.assertEqual(len(self._new_mails), 2, 'Should have created 2 mail.mail (1 for users, 1 for customers)')
-        self.assertEqual(len(self._new_mails.exists()), 2, 'Should not have deleted mail.mail records')
-
     @users('employee')
     @mute_logger('odoo.tests', 'odoo.addons.mail.models.mail_mail', 'odoo.models.unlink')
     def test_mail_composer_post_parameters(self):