App indicator adds an entry for each snap launch

[David Planella]

Snaps that use the app indicator area via Qt add an new entry to it every time they are launched, instead of reusing the existing entry.

Steps to reproduce and screenshot:
https://github.com/nuttyartist/notes/pull/77

Some research:

- Uses http://doc.qt.io/qt-5/qsystemtrayicon.html
- didrocks mentions that this might be related to bug 1600136, that is /tmp is not being reused between run instances

[Didier Roche-Tolomelli (didrocks)]

Ok, so to be a little bit more verbose on the issue there,

What happens if for the indicator to apps communication, a socket is created and stamped in /tmp. That enabled in case of app crash to create a new indicator appmenu entry.

What I think is happening is, as with snapd, we create a new /tmp everytime (and not being accessible to the system with the same address, see other bug report), a new instance is created.

[Didier Roche-Tolomelli (didrocks)]

(everytime as "everytime an instance is executed")

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[John Lenton (chipaca)]

We no longer create a new /tmp per run, so this should be fixed. Please reopen if not.