[Merge] lp:~yuningdodo/ubuntu/trusty/unity-settings-daemon/unity-settings-daemon.lp1396464-set-volume-to-zero-before-mute into lp:ubuntu/trusty-updates/unity-settings-daemon

[Yu Ning]

David, when the bug #1396464 is reproduced I dump the volume value and is_muted by adding some printf() and found is_muted is true while volume is not zero, however to be honest I don't know the root cause, the underlying logic in unity-settings-daemon and unity-control-center is complicated and I didn't find out how this inconsistency finally leads to the loop. My patch is only a toplevel workaround, it didn't fix the internal logic trap, if there is any.
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https://code.launchpad.net/~yuningdodo/ubuntu/trusty/unity-settings-daemon/unity-settings-daemon.lp1396464-set-volume-to-zero-before-mute/+merge/242869
Your team Ubuntu Development Team is requested to review the proposed merge of lp:~yuningdodo/ubuntu/trusty/unity-settings-daemon/unity-settings-daemon.lp1396464-set-volume-to-zero-before-mute into lp:ubuntu/trusty-updates/unity-settings-daemon.