Hitbox and eye level of polar bear is not adjusted when attacking

Repost of MC-142848 for Bedrock Edition. For more information about this bug, read the section about polar bears in this article: https://www.minecraft.net/en-us/article/how-crawling-came-minecraft

The bug

The hitbox of a polar bear is not adjusted when it is attacking. This might be unintuitive for the player when they try to fight against the polar bear.

How to reproduce

1. Spawn a polar bear
2. Switch to survival mode
3. Hit the polar bear
4. When it attacks, try to hit it in the upper half of its body while it's standing up