Prevents potential multiple evaluations of enumerable.
# Conflicts: # osu.Game/Screens/Multi/Match/MatchSubScreen.cs # osu.Game/Screens/Multi/Multiplayer.cs # osu.Game/Screens/Multi/MultiplayerSubScreen.cs # osu.Game/Screens/OsuScreen.cs # osu.Game/osu.Game.csproj # osu.sln
Closes #1757
No big optimizations yet, but groundwork is laid out.