[Merge] lp:~rsalveti/ubuntu-touch-session/changing-config-allow-volume-per-role into lp:ubuntu-touch-session

[Ricardo Salveti]

To be used/tested with https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/landing-018.
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https://code.launchpad.net/~rsalveti/ubuntu-touch-session/changing-config-allow-volume-per-role/+merge/235563
Your team Ubuntu Phablet Team is requested to review the proposed merge of lp:~rsalveti/ubuntu-touch-session/changing-config-allow-volume-per-role into lp:ubuntu-touch-session.