Skull doesn't appear on a Giant

What I expected to happen was...:
The Giant should have my Minecraft head.

What actually happened was...:
My head doesn't appear on the Giant

Steps to Reproduce:
1.Give you a command block and type this command:
/summon Giant ~ ~2 ~ {Equipment:[{},{},{},{},{id:skull,Damage:3,tag:{SkullOwner:SlimyRedstone}}]}

2.Trigger the command block