I have reproduced the traceback with apparmor 2.8.95~2430-0ubuntu5.1 from trusty-updates, and can confirm that apparmor 2.8.95~2430-0ubuntu5.2 from trusty-proposed fixes the problem. Marking verification-done.
I have reproduced the traceback with apparmor 2.8.95~ 2430-0ubuntu5. 1 from trusty-updates, and can confirm that apparmor 2.8.95~ 2430-0ubuntu5. 2 from trusty-proposed fixes the problem. Marking verification-done.