[FIX] base_user_role: update users' groups when a role is deleted

base_user_role/models/role.py

@@ -46,6 +46,13 @@ class ResUsersRole(models.Model):
         self.update_users()
         return res
 
+    @api.multi
+    def unlink(self):
+        users = self.mapped('user_ids')
+        res = super(ResUsersRole, self).unlink()
+        users.set_groups_from_roles()
+        return res
+
     @api.multi
     def update_users(self):
         """Update all the users concerned by the roles identified by `ids`."""