[MC-146097] Boat Floor clip

If you get out of a boat on land you clip through the ground.

Environment

Using Lenovo Legion Y520, GeForce GTX 1060

Java 1.8 I think.

For getting damage when exiting the boat, see MC-136367. For the frame issues when turning in the boat, see MC-145731.

neither of these links show going into the floor

This issue happens a whole lot with moving other entities like villagers. They clip through the ground on an almost consistent basis.