[Merge] lp:~mathieu-tl/mtp/lp1421664 into lp:mtp

[Sebastien Bacher]

oh, I guess the reason is that the -o runs the second test even when the first one is invalid, or $disconnected is not a number in that case and that leads to the error
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https://code.launchpad.net/~mathieu-tl/mtp/lp1421664/+merge/249669
Your team Ubuntu Phablet Team is requested to review the proposed merge of lp:~mathieu-tl/mtp/lp1421664 into lp:mtp.