The NBT Tags ArmorItems and HandItems no longer work

When attempting to use either the NBT tag ArmorItems or HandItems, the mob you are summoning will not have the item. I have used the command /summon minecraft:zombie ~0 ~1 ~0 {HandItems:[

{id:diamond_sword}

,{}]} and /summon minecraft:zombie ~0 ~1 ~0 {ArmorItems:[{},{},{},

{id:chainmail_helmet}

]}.