Bug 1061438 - [Ringtones] Fix wording for managing alerts

I'd have to do basically the same thing I do here in get() to get the type. Or I could change how IDs are built, but that could confuse dogfooders. If they'd picked an SD card ringtone back when we used the old IDs, we wouldn't show them as selected in the "Select Sound" activity. I was doing this to work around that problem...