Horse and Rider Can Take Damage As Soon As Player Mounts

Verification builds:
1.1.0.0

Summary:
Horses somehow die as soon as a player tries to mount them. They also seem to randomly take damage at other times.

Steps to Reproduce:

1. Tame a horse and Equip with saddle
2. Ride the horse, dismount, then mount the horse again
3. It has a high chance of dying randomly

Observed Results:
Horse takes damage or dies when the player mounts. Also has a chance to take damage when equipped with a saddle.

Expected Results:
Horses should not take damage from mounting, or normal riding

Screenshots/Videos attached: Yes
Youtube

Notes:

• This may be a regression of an earlier bug whereby clients would cause horse damage by dismounting and jumping (eg MCPE-15218)
• Horses also appear to take damage if you mount them and then equip a saddle
• If the horse has received fall damage previously, it almost guarantees that it will take further damage when the player mounts it.
• Test world attached