[1.8] Adventure's dream's Mooshroom is missing it's legs

Partner Rank: 2

Partner Team Reporting: Noxcrew

Verification builds and Platforms: ver. 1.8.4.0, build 1235442, Win10

Summary:
Due to the backend changes the mooshroom no longer has legs 

Impact:
This makes the mooshroom appear to be floating and appear broken

Repro Steps:

1. Download Adventure's Dream from the Marketplace.
2. Create a world in Creative with the Adventure's Dream resource pack enabled 
3. Type "/summon mooshroom"
4. Observe the broken mooshroom model

Observed Results:
The mooshroom has no legs 

Expected Results:
The mooshroom has legs 

 Screenshots/Videos attached: Yes/No

Yes, a screenshot has been attached.

Regression Builds:

This did not occur in Beta 1.7.7

Notes:
I believe this is due to the removal of quadruped model which the mooshroom inherits. Due to the game no longer supporting the quadruped bones our model broke. In Adventure's dream the cow and mooshroom are different models.