Flying around fast in large bodies of water while having the pie chart open generates log spam

Steps to reproduce:

1. Generate a superflat world with the "Water World" preset.
2. Fly down under the water surface.
3. Set your gamemode to spectator and turn the flying speed up to the maximum.
4. Open the debug pie chart.
5. Fly around in the water.
6. Different warnings get outputted in the log at high frequency (see attached images). Warnings also sometimes occur when the game is paused/unpaused while in the water (see the "root" spam in the second image).