Fix MC-154214 (#2195)

This should resolve unloading issues.

Spigot-Server-Patches/Fix-MC-154214.patch

@@ -0,0 +1,48 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Spottedleaf <Spottedleaf@users.noreply.github.com>
+Date: Sun, 16 Jun 2019 23:30:25 -0700
+Subject: [PATCH] Fix MC-154214
+
+Avoid adding player tickets when they're out of range of the closest player
+
+diff --git a/src/main/java/net/minecraft/server/ChunkMapDistance.java b/src/main/java/net/minecraft/server/ChunkMapDistance.java
+index 705ca68798..799c134e4b 100644
+--- a/src/main/java/net/minecraft/server/ChunkMapDistance.java
++++ b/src/main/java/net/minecraft/server/ChunkMapDistance.java
+@@ -0,0 +0,0 @@ public abstract class ChunkMapDistance {
+         }
+ 
+         private void a(long i, int j, boolean flag, boolean flag1) {
++            final long chunkPosition = i; // Paper - conflict on variable change
+             if (flag != flag1) {
+                 Ticket<?> ticket = new Ticket<>(TicketType.PLAYER, ChunkMapDistance.b, new ChunkCoordIntPair(i), ChunkMapDistance.this.currentTick);
+ 
+                 if (flag1) {
+                     ChunkMapDistance.this.m.a(ChunkTaskQueueSorter.a(() -> { // Paper - decompile fix
+                         ChunkMapDistance.this.p.execute(() -> {
++                            // Paper start - Fix MC-154214
++                            if (!this.inRange(this.getNearestDistanceFromPlayerMap().get(chunkPosition))) {
++                                return;
++                            }
++                            // Paper end
+                             ChunkMapDistance.this.a(i, ticket);
+                             ChunkMapDistance.this.o.add(i);
+                         });
+@@ -0,0 +0,0 @@ public abstract class ChunkMapDistance {
+ 
+         }
+ 
++        private final boolean inRange(int distance) { return this.c(distance); } // Paper - OBFHELPER
+         private boolean c(int i) {
+             return i <= this.e - 2;
+         }
+@@ -0,0 +0,0 @@ public abstract class ChunkMapDistance {
+ 
+     class b extends ChunkMap {
+ 
+-        protected final Long2ByteMap a = new Long2ByteOpenHashMap();
++        protected final Long2ByteMap a = new Long2ByteOpenHashMap(); protected final Long2ByteMap getNearestDistanceFromPlayerMap() { return this.a; } // Paper - OBFHELPER
+         protected final int b;
+ 
+         protected b(int i) {
+--