Invalid Variant value for llama does not default to 0 causing invisible llama

The bug

When you change the value of the Variant tag to an invalid value (smaller than 0 or larger than 3) the value if not defaulted to 0 causing the llama to be invisible.

How to reproduce

Try this in a seperate test world, dealing damage to the llama will cause your screen to turn black.

/summon llama ~ ~ ~ {Variant:4}