[MC-51354] Placing head in single player sometimes crashes game

Placing a head given by

/give @p minecraft:skull 1 3 {SkullOwner:kurisubrooks}

to the player crashes the game.

Description: Handling packet

java.util.ConcurrentModificationException
	at java.util.LinkedList$ListItr.checkForComodification(Unknown Source)
	at java.util.LinkedList$ListItr.next(Unknown Source)
	at com.google.common.collect.Iterators$9.next(Iterators.java:939)
	at com.google.common.collect.Iterators.addAll(Iterators.java:357)
	at com.google.common.collect.Lists.newArrayList(Lists.java:147)
	at oy.a(SourceFile:179)
	at oy.c(SourceFile:163)
	at oy.a(SourceFile:116)
	at att.d(SourceFile:88)
	at att.a(SourceFile:77)
	at ahf.a(SourceFile:79)
	at agh.a(SourceFile:122)
	at od.a(SourceFile:307)
	at on.a(SourceFile:411)
	at kt.a(SourceFile:59)
	at kt.a(SourceFile:10)
	at fn.a(SourceFile:163)
	at oi.c(SourceFile:134)
	at net.minecraft.server.MinecraftServer.w(SourceFile:565)
	at net.minecraft.server.MinecraftServer.v(SourceFile:481)
	at cek.v(SourceFile:128)
	at net.minecraft.server.MinecraftServer.run(SourceFile:397)
	at mq.run(SourceFile:667)