Remove World.FrameNumber.

OpenRA.Game/Sound.cs

@@ -518,8 +518,7 @@ namespace OpenRA
 				return null;
 			}
 
-			var world = Game.orderManager.world;
-			int currFrame = world != null ? world.FrameNumber : 0;
+			var currFrame = Game.orderManager.LocalFrameNumber;
 			float atten = 1f;
 
 			// Check if max # of instances-per-location reached:

OpenRA.Game/Traits/World/Shroud.cs

@@ -61,7 +61,7 @@ namespace OpenRA.Traits
 
 		void Invalidate()
 		{
-			Hash = Sync.hash_player(self.Owner) + self.World.FrameNumber * 3;
+			Hash = Sync.hash_player(self.Owner) + self.World.WorldTick * 3;
 		}
 
 		static IEnumerable<CPos> FindVisibleTiles(World world, CPos position, WRange radius)

OpenRA.Game/World.cs

@@ -30,7 +30,6 @@ namespace OpenRA
 		List<IEffect> effects = new List<IEffect>();
 		Queue<Action<World>> frameEndActions = new Queue<Action<World>>();
 
-		public int FrameNumber { get { return orderManager.LocalFrameNumber; } }
 		public int Timestep;
 
 		internal readonly OrderManager orderManager;