Bug 1080556 - Intermittent bluetooth/test/unit/transfer_test.js r=timdre...

...am
I think that another solution would be to force a setTimeout a few lines down:

    requireApp('bluetooth/js/transfer.js', function() {
      setTimeout(done);
    });

This will queue the `done` function to run after the callback passed to MockL10n's `mozL10n.once`.