If you create a Chested Normal Horse with a /summon Command and try to put an item in the chest, the game crashes.

Put the summary of the bug you're having here

What I expected to happen was...:
You can put items in the Horsechest and take them out.

What actually happened was...:
The game crashes.

Steps to Reproduce:
1. Start the game
2. Use the Command /summon EntityHorse ~ ~ ~ {Tame:1,Type:0,Saddle:1,ChestedHorse:1}
3. Sit on the Horse
4. Put an item in the Horsechest.