Monsters do not render armour properly

Armour on monsters (zombies, zombie pigmen, skeletons) and their baby variants is not visible, though it applies all effects normally amd drops when the mob is killed. On skeletons, it can still be seen through their ribcages, suggesting that it has been scaled incorrectly.

Original Report: Found this bug on the new update 0.13.1
i added a screenshots below

UPDATE FOR 0.14.0 BETA
Zombie Pigman armor doesn't render properly still

UPDATE FOR 0.15.4
Still affects Pigman, but now Strays

Update by [Mojang] Adrian Östergård
This bug has been reported to our internal bug tracker for further testing and a fix. It is scheduled to be fixed in one of the future updates (no specific date can be provided).
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