Update upstream CB

Spigot-Server-Patches/MC-124833.patch

@@ -0,0 +1,26 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Zach Brown <1254957+zachbr@users.noreply.github.com>
+Date: Wed, 4 Apr 2018 21:00:43 -0400
+Subject: [PATCH] MC-124833
+
+Conflicting reports of what software this bug does and does not affect.
+Given the trivial impact of fixing it and an overabundance of caution,
+we'll patch it in Paper as well. This will probably be a short lived
+patch, with it being fixed in Vanilla proper 1.13
+
+diff --git a/src/main/java/net/minecraft/server/EntityItemFrame.java b/src/main/java/net/minecraft/server/EntityItemFrame.java
+index 8b806c303..f0d6d6b85 100644
+--- a/src/main/java/net/minecraft/server/EntityItemFrame.java
++++ b/src/main/java/net/minecraft/server/EntityItemFrame.java
+@@ -0,0 +0,0 @@ public class EntityItemFrame extends EntityHanging {
+             }
+ 
+             itemstack.a((EntityItemFrame) null);
++
++            // Paper - MC-124833 - conflicting reports of what server software this does and doesn't affect.
++            // It's a one liner with near-zero impact so we'll patch it anyway just in case
++            this.setItem(ItemStack.a); // OBFHELPER - ItemStack.EMPTY
+         }
+     }
+ 
+--

work/CraftBukkit

@@ -1 +1 @@
-Subproject commit 68b4fb64275baa884858f0483681e6470d4afa6c
+Subproject commit fb423b8f48335d0dc6c88cd8a24ee07d82ae09a8