Don't process despawn if entity is in a chunk scheduled for unload

This won't happen anyways if the user has
"skip ticking for entities in chunks scheduled for unload" turned on,
but if they don't, protect from this instant killing the entity to
keep it vanilla in behavior

a player may teleport away, and trigger instant despawn

Spigot-Server-Patches/0333-Don-t-process-despawn-if-entity-is-in-a-chunk-schedu.patch

@@ -0,0 +1,29 @@
+From 4b0d74a924803d09ea2ba1e95f38afc4de96d86f Mon Sep 17 00:00:00 2001
+From: Aikar <aikar@aikar.co>
+Date: Thu, 19 Jul 2018 01:23:00 -0400
+Subject: [PATCH] Don't process despawn if entity is in a chunk scheduled for
+ unload
+
+This won't happen anyways if the user has
+"skip ticking for entities in chunks scheduled for unload" turned on,
+but if they don't, protect from this instant killing the entity to
+keep it vanilla in behavior
+
+a player may teleport away, and trigger instant despawn
+
+diff --git a/src/main/java/net/minecraft/server/EntityInsentient.java b/src/main/java/net/minecraft/server/EntityInsentient.java
+index 89e878365..d6a1933ad 100644
+--- a/src/main/java/net/minecraft/server/EntityInsentient.java
++++ b/src/main/java/net/minecraft/server/EntityInsentient.java
+@@ -628,6 +628,8 @@ public abstract class EntityInsentient extends EntityLiving {
+         if (this.persistent) {
+             this.ticksFarFromPlayer = 0;
+         } else {
++            Chunk currentChunk = getChunkAtLocation(); // Paper
++            if (currentChunk != null && (currentChunk.isUnloading() || currentChunk.scheduledForUnload != null)) return; // Paper
+             EntityHuman entityhuman = this.world.findNearbyPlayer(this, -1.0D);
+ 
+             if (entityhuman != null && entityhuman.affectsSpawning) { // Paper - Affects Spawning API
+-- 
+2.18.0
+