Workaround for really evil plugins breaking sounds

Some plugins are doing really really bad things to worlds breaking the
ability to send sounds to some users.

So creating another reference to the player chunk map that plugins wont be breaking, and
print a stack trace at world creation if we ever get an expected world state to identify
who is doing it!

If we encounter this illegal state, we fall back to the old method of sending sounds, so
sending sounds will still work, just less effecient.

Spigot-Server-Patches/0531-Optimize-sending-packets-to-nearby-locations-sounds-.patch

@@ -11,10 +11,10 @@ This will drastically cut down on packet sending cost for worlds with
 lots of players in them.
 
 diff --git a/src/main/java/net/minecraft/server/PlayerList.java b/src/main/java/net/minecraft/server/PlayerList.java
-index 9b726de6daeba42120f3a948fbdcf080d0e72917..269580ae2a6edca979ccc1e46df144468ea70a18 100644
+index 9b726de6daeba42120f3a948fbdcf080d0e72917..ada082e67ac8a3e79bab5b360f09c9402f683b86 100644
 --- a/src/main/java/net/minecraft/server/PlayerList.java
 +++ b/src/main/java/net/minecraft/server/PlayerList.java
-@@ -1027,11 +1027,27 @@ public abstract class PlayerList {
+@@ -1027,11 +1027,30 @@ public abstract class PlayerList {
              world = (WorldServer) entityhuman.world;
          }
  
@@ -24,26 +24,50 @@ index 9b726de6daeba42120f3a948fbdcf080d0e72917..269580ae2a6edca979ccc1e46df14446
 -            if (!(entity instanceof EntityPlayer)) continue;
 -            EntityPlayer entityplayer = (EntityPlayer) entity;
 +        // Paper start
-+        if (world == null && dimensionmanager != null) {
++        if ((world == null || world.chunkProvider == null) && dimensionmanager != null) {
 +            world = dimensionmanager.world;
 +        }
 +        if (world == null) {
 +            LOGGER.error("Sending packet to invalid world" + entityhuman + " " + dimensionmanager + " - " + packet.getClass().getName(), new Throwable());
 +            return; // ??? shouldn't happen...
 +        }
-+        ChunkProviderServer chunkProvider = (ChunkProviderServer) world.chunkProvider;
-+        if (chunkProvider == null) {
-+            // ??? Shouldn't be possible but seem some hacky plugins apparently do hack things.
-+            return;
++        PlayerChunkMap chunkMap = world.chunkMap;
++        Object[] backingSet;
++        if (chunkMap == null) {
++            // Really shouldn't happen...
++            backingSet = world.players.toArray();
++        } else {
++            com.destroystokyo.paper.util.misc.PooledLinkedHashSets.PooledObjectLinkedOpenHashSet<EntityPlayer> nearbyPlayers = chunkMap.playerViewDistanceBroadcastMap.getObjectsInRange(MCUtil.fastFloor(d0) >> 4, MCUtil.fastFloor(d2) >> 4);
++            if (nearbyPlayers == null) {
++                return;
++            }
++            backingSet = nearbyPlayers.getBackingSet();
 +        }
-+        com.destroystokyo.paper.util.misc.PooledLinkedHashSets.PooledObjectLinkedOpenHashSet<EntityPlayer> nearbyPlayers = chunkProvider.playerChunkMap.playerViewDistanceBroadcastMap.getObjectsInRange(MCUtil.fastFloor(d0) >> 4, MCUtil.fastFloor(d2) >> 4);
-+        if (nearbyPlayers == null) {
-+            return;
-+        }
-+        Object[] backingSet = nearbyPlayers.getBackingSet();
++
 +        for (Object object : backingSet) {
 +            if (!(object instanceof EntityPlayer)) continue;
 +            EntityPlayer entityplayer = (EntityPlayer) object;
              // Paper end
  
              // CraftBukkit start - Test if player receiving packet can see the source of the packet
+diff --git a/src/main/java/net/minecraft/server/WorldServer.java b/src/main/java/net/minecraft/server/WorldServer.java
+index 9e32e2db10f5faaa3c5f4adc5cbc2c1a2e4d3073..854c97bddb711ed252c2ae8398247641fdfb10be 100644
+--- a/src/main/java/net/minecraft/server/WorldServer.java
++++ b/src/main/java/net/minecraft/server/WorldServer.java
+@@ -70,6 +70,7 @@ public class WorldServer extends World {
+         }
+     }
+     // Paper end
++    public final PlayerChunkMap chunkMap; // Paper
+     private final MinecraftServer server;
+     private final WorldNBTStorage dataManager;
+     public boolean savingDisabled;
+@@ -208,6 +209,8 @@ public class WorldServer extends World {
+         }, gameprofilerfiller, false, gen, env);
+         this.pvpMode = minecraftserver.getPVP();
+         worlddata.world = this;
++        if (chunkProvider == null) { chunkMap = null; new Throwable("World created without a ChunkProvider!").printStackTrace(); } // Paper - figure out if something weird happened here
++        else chunkMap = ((ChunkProviderServer) chunkProvider).playerChunkMap;
+         // CraftBukkit end
+         if (com.destroystokyo.paper.PaperConfig.useOptimizedTickList) {
+             this.nextTickListBlock = new com.destroystokyo.paper.server.ticklist.PaperTickList<>(this, (block) -> { // Paper - optimise TickListServer