Affected Version:
2.5.1
What steps will reproduce the problem?
1. Submit a code review to gerrit
2. Look at first message source and see it has a in-reply-to but the parent has not been sent.
What is the expected output? What do you see instead?
If you get added to do a review, it sends a mail notification asking you to do code review, this contains the correct message-id for a parent mail notification and all mail notifications for comments have the correct in-reply-to id. If you submit a patch to gerrit you get only get a mail notification for patch comments. The first comment has the in-reply-to that points to a non existent parent mail notification.