Bug 1104057 - Connect standaloneUI with the BasicRoom

Bug https://bugzilla.mozilla.org/show_bug.cgi?id=1104002 just landed. I encourage you to rebase this work on top of that bug and reuse the ```Rooms.get()``` call at https://github.com/mozilla-b2g/firefoxos-loop-client/blob/master/app/js/helpers/room/room_controller.js#L73