Remove unused assets from torbutton (preferences-mobile.css)
We still have a pair of CSS files and other assets that we should have removed a while ago (I don't remember the exact issue number, now).
toolkit/torbutton/chrome/skin/preferences.css(to double check)
aboutTor.xhtml, and hidden by
aboutTor.csswhenever we're not in mobile mode, which doesn't happen anymore, at the moment)