Issue Assigned event is not sending emails using 'Inline Assign'

Steps to produce:

1. Create a project with notification scheme.
2. Set the Issue Assigned to Current Assignee. Make sure in the notification scheme, only Issue Assigned is triggered when the issue is assigned (you can clear Issue Updated event since is triggered when the issue is assigned).
3. Assign the issue to anyone using 'Inline Assign' NOT using the 'Assign' button.

Actual Results
Emails are not sent.

Expected Results
JIRA should send out the email notifications in the same way using the 'Assign' button.