1. impact of the bug is minimal for stable releases, since apport is disabled by default. However, being able to run 'ubuntu-bug', 'apport-bug' or 'apport-collect' is useful for developers trying to get more information from users.
2. This has not been addressed in the development branch (it isn't open yet).
3. Patch is very small. See comment #1.
4. TEST CASE:
$ apport-bug -p apparmor --save /tmp/apport.txt
You should be prompted by sudo at this point.
5. The regression potential of the patch is very low, as it updates the apport hook which is not enabled by default in the stable releases.