[FIX] mail: use contact app icon for partner-related activities in systray

As res.partner model is defined in base systray takes the base icon as icon
used in the systray when classifying activities by model. As base module has
no icon it leads to a blank icon being displayed in the systray. Purpose of
this commit is to use the icon from Contact application instead.

As contacts application now depends on mail we do it simply through
inheriting the systray_get_activities method that return the data to display
the systray elements.

This commit is linked to task ID 1882545 and PR #26797.

addons/contacts/__init__.py

@@ -1,2 +1,4 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from . import models

addons/contacts/models/__init__.py

@@ -0,0 +1,4 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from . import res_users

addons/contacts/models/res_users.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo import api, models, modules
+
+
+class Users(models.Model):
+    _name = 'res.users'
+    _inherit = ['res.users']
+
+    @api.model
+    def systray_get_activities(self):
+        """ Update the systray icon of res.partner activities to use the
+        contact application one instead of base icon. """
+        activities = super(Users, self).systray_get_activities()
+        for activity in activities:
+            if activity['model'] != 'res.partner':
+                continue
+            activity['icon'] = modules.module.get_module_icon('contacts')
+        return activities