Boats no longer negate fall damage

Falling from a height in a boat deals fall damage when the intended mechanic is to not deal damage, see MCPE-149490 / MC-105103.

Steps to Reproduce:

1. Build a platform high in the air
2. Place a boat on the platform
3. Get in the boat
4. Switch to Survival mode
5. Ride the boat off the platform

Observed Results:
The player takes fall damage.

Expected Results:
Boats should negate fall damage.