When spawning an Iron Golem on leaves it gets stuck

What I expected to happen was...:
The Iron Golem should have fallen to the ground like any other mob. **

What actually happened was...:
The Iron Golem got stuck in the leaves and was able to be pushed inside of the block.

Steps to Reproduce:
1. Utilizing the Iron Golem Spawn Egg, spawn an Iron Golem on a bunch of leaves (3x1 should work) or a tree (any type).
2. The Iron Golem should be standing on the leaves
3. Push the Iron Golem into the tree using your player