Remove KeyedObject interface (#7680)

patches/server/0358-Fix-items-vanishing-through-end-portal.patch

@@ -0,0 +1,28 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: AJMFactsheets <AJMFactsheets@gmail.com>
+Date: Wed, 22 Jan 2020 19:52:28 -0600
+Subject: [PATCH] Fix items vanishing through end portal
+
+If the Paper configuration option "keep-spawn-loaded" is set to false,
+items entering the overworld from the end will spawn at Y = 0.
+
+This is due to logic in the getHighestBlockYAt method in World.java
+only searching the heightmap if the chunk is loaded.
+
+Quickly loading the exact world spawn chunk before searching the
+heightmap resolves the issue without having to load all spawn chunks.
+
+diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
+index 44fb916fafdc4eb9c4c7971b9c53f7f3bc00b431..361d8fc7cfbeb8b80b6e99ab61930596710c3bf5 100644
+--- a/src/main/java/net/minecraft/world/entity/Entity.java
++++ b/src/main/java/net/minecraft/world/entity/Entity.java
+@@ -3031,6 +3031,9 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource {
+             if (flag1) {
+                 blockposition1 = ServerLevel.END_SPAWN_POINT;
+             } else {
++                // Paper start - Ensure spawn chunk is always loaded before calculating Y coordinate
++                destination.getChunkAt(destination.getSharedSpawnPos());
++                // Paper end
+                 blockposition1 = destination.getHeightmapPos(Heightmap.Types.MOTION_BLOCKING_NO_LEAVES, destination.getSharedSpawnPos());
+             }
+             // CraftBukkit start