interfaces: updates default, mir, optical-observe, system-observe, screen-inhibit-control and unity7

[jdstrand]

• interfaces/unity7: allow dbus introspection for dbusmenu
• interfaces/unity7: allow access to DBus properties for /org/a11y/bus
• interfaces/screen-inhibit-control: allow alternate object paths under Unity
• interfaces/optical-drive: allow read on /proc/sys/dev/cdrom/info
• interfaces/system-observe: remove @{PROC}/meminfo already in base abstraction
• interfaces/default: allow owner read on @{PROC}/@{pid}/loginuid for logger
• interfaces/mir: don't log noisy access to lttng files (just like in unity7)
• interfaces/default: backport change from AppArmor 2.12 for perl-base

Note that the change for @{PROC}/meminfo removal from interfaces/system-observe is safe to at least Ubuntu 12.04. The removal was at the request of the QA team since they were doing rule-by-rule tests and since it was already allowed be the interface, connecting/disconnecting the interface had no effect on policy (for this specific rule).

[codecov-io]

Codecov Report

Merging #3531 into master will increase coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3531      +/-   ##
==========================================
+ Coverage   76.79%   76.79%   +<.01%     
==========================================
  Files         379      379              
  Lines       26309    26309              
==========================================
+ Hits        20203    20205       +2     
+ Misses       4308     4306       -2     
  Partials     1798     1798

Impacted Files	Coverage Δ
interfaces/builtin/optical_drive.go	100% <ø> (ø)	⬆️
interfaces/builtin/screen_inhibit_control.go	100% <ø> (ø)	⬆️
interfaces/builtin/mir.go	68.75% <ø> (ø)	⬆️
interfaces/builtin/system_observe.go	100% <ø> (ø)	⬆️
interfaces/builtin/unity7.go	76.66% <ø> (ø)	⬆️
cmd/snap/cmd_aliases.go	96% <0%> (+2%)	⬆️
interfaces/sorting.go	96.66% <0%> (+3.33%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 2a0e619...4d7ce93. Read the comment docs.

[mvo5]

Thanks!

[zyga]

LGTM, I'd like to merge master before it goes in though (green-tests)