Giants will not move.

I summoned a giant.
What I expected to happen was it will start attacking the snowman I made.
What actually happened was the giant did nothing but get hit by the snowman snow ball. I went to Minecraft 1.7.9 and the giant did attack the snowman but in Minecraft 14w25b it did not attack.

Steps to Reproduce:
1. Summon a giant.
2. Go in survival mode or make something that will attack it.
3. Get close to the giant and it will not chase you and just stand there.