I tried giving myself a head with the {SkullOwner:} tag in the snapshot.
The specific command I used was*: /give @p player_head{SkullOwner:colin} 1*
It instantly closed my world and was stuck on the saving screen for 20 mins before I gave up and closed Minecraft in task manager. 

When I restarted the game and rejoined the world, everything was saved correctly and the head was in my inventory.