Boat won't float in 18w22b.

Put the summary of the bug you're having here

What I expected to happen was...:
...for boats to float.

What actually happened was...:
...they sank to bottom of swamp/ocean.

Steps to Reproduce:
1. Put a boat (Birch) out into the water and it sank to bottom.
2. Tried another type of boat (Oak) same result. It sank.
3. ...