Random song selection broken with Tile/Chessboard

[jose1711]

Steps to reproduce

1. Create a playlist containing two random songs
2. [in game settings] Set Songmenu to Tile (or Chessboard)
3. Enter Party mode, Mode: Classic, Song selection: Playlist, Song selection: saved playlist
4. Number of teams: 2
5. Observe the results of selection, advance to next selection using jokers (1-2)

Expected behaviour

Only the songs from playlist should be presented

Actual behaviour

Different songs are being picked

Workaround

Set songmenu to any value other than Tile or Chessboard

Details

Provide some additional information:

• USDX version: git, commit 1ba4ac57
• Operating System + version: Arch Linux, current to Oct 14 2019

[barbeque-squared]

@jose1711 can you build the version from #665 (or wait until the CI is done and grab one of the artifacts) and see if that mostly solves your issue? It won't be a fix in 100% of the cases, but should at least make it less unplayable than it is right now

[barbeque-squared]

I'll leave this open for the time being. The behaviour is much better now (especially if your playlist contains significantly more songs than there are party rounds) but the original bug will still occur quite frequently when a two-song playlist is used.

By the way, a quicker way of testing/reproducing this: just load the playlist in the regular Song selection screen (or search for something that ends up with only two songs) and start pressing random. Works best if the two songs are somewhere in the middle of your song library (ie not any of the first or last two).