*What I expected to happen was:
The players head beeing inside the barrier block resulting in some sort of x-ray machine

*What actually happened was:
The game froze and then crashed. Upon reloging the block was gone

*Steps to Reproduce:
1. Load up a world in 14w05a
2. Type the following command: /setblock ~ ~1 ~ minecraft:barrier

java.lang.NullPointerException: Unexpected error
	at bpv.a(SourceFile:540)
	at bpv.b(SourceFile:514)
	at bpq.b(SourceFile:680)
	at bpq.a(SourceFile:1236)
	at bpq.b(SourceFile:921)
	at bcf.ag(SourceFile:803)
	at bcf.f(SourceFile:730)
	at net.minecraft.client.main.Main.main(SourceFile:154)