Uses GetContainingInputManager instead, as per framework changes.
This also - Renames TextAwesome to SpriteIcon. - Removes the default size of "20" from SpriteIcon (now defaults to the underlying texture size).
Welcome back BeatmapManager
Fixes race condition when API returns a failure after exiting song select. Note that the API does also schedule to the correct thread, but this schedule ensures the callback is never run, which is what we want in this case.
Hide database functionality at a lower level in preparation from eventually making it private.