The hostility of mobs over other mobs are broken on peaceful mode

Mobs that are usually aggressive to other mobs no longer do on peaceful mode

For example:

• Polar bears no longer tries to attack foxes
• Foxes no longer tries to attack chicken
• Snow Golems no longer tries to attack shulkers

This bug was discovered by Ilmango on his pre-release 3 video: https://youtube.com/watch?v=QVHvd5IEQTA&t=4m14s