The texture of chainmail helmets on baby humanoid mobs has no transparent pixels on its top, unlike on adult mobs

The top side of chainmail helmets worn by baby hostile mobs (such as zombies) are missing transparent pixels, which is inconsistent with chainmail helmets worn by adult hostile mobs.

To reproduce the bug, choose one of the two methods below:

1. Throw a chainmail helmet on the ground at the feet of a zombie baby (or any other humanoid hostile mob) until it picks it up;

2. Summon a zombie baby with a chainmail helmet using the command:

/summon zombie ~ ~ ~ {equipment:{head:{id:chainmail_helmet}}}

Expected result: Some pixels on the top side of the chainmail helmet should be transparent.

Actual result: Some pixels on the top side of the chainmail helmet are not transparent.