[9.0][FIX][mail_tracking] Control exception when mail_message was removed (#132)

mail_tracking/__openerp__.py

@@ -5,7 +5,7 @@
 {
     "name": "Email tracking",
     "summary": "Email tracking system for all mails sent",
-    "version": "9.0.3.0.0",
+    "version": "9.0.3.0.1",
     "category": "Social Network",
     "website": "http://www.tecnativa.com",
     "author": "Tecnativa, "

mail_tracking/models/mail_tracking_email.py

@@ -224,6 +224,8 @@ class MailTrackingEmail(models.Model):
         return email
 
     def _message_partners_check(self, message, message_id):
+        if not self.mail_message_id.exists():  # pragma: no cover
+            return True
         mail_message = self.mail_message_id
         partners = (
             mail_message.needaction_partner_ids | mail_message.partner_ids)