SPIGOT-3067: Wither skeleton heads not dropping

nms-patches/EntitySkeletonWither.patch

@@ -0,0 +1,19 @@
+--- a/net/minecraft/server/EntitySkeletonWither.java
++++ b/net/minecraft/server/EntitySkeletonWither.java
+@@ -36,7 +36,7 @@
+     }
+ 
+     public void die(DamageSource damagesource) {
+-        super.die(damagesource);
++        // super.die(damagesource); // CraftBukkit
+         if (damagesource.getEntity() instanceof EntityCreeper) {
+             EntityCreeper entitycreeper = (EntityCreeper) damagesource.getEntity();
+ 
+@@ -45,6 +45,7 @@
+                 this.a(new ItemStack(Items.SKULL, 1, 1), 0.0F);
+             }
+         }
++        super.die(damagesource); // CraftBukkit - moved from above
+ 
+     }
+