Lightning gives AI to Witches and Zombie Pigman that were originally Pigs and Villagers that had NoAI set to 1

Lightning can give AI to pigs or villagers who originally had the NoAI NBT tag set to 1.

What I expected to happen was...:
The AI-less pigs or villagers stay at their respective forms when they are struck by lightning.

What actually happened was...:
The AI-less pig or villager actually changed into a zombie pigman or witch with AI.

Steps to Reproduce:
1. Summon a pig or villager using /summon ~ ~ ~ Pig

{NoAi:1}

or /summon ~ ~ ~ Villager

{NoAI:1}

2. Summon a lightning bolt using /summon LightningBolt.

3. The two mobs become a witch or zombie pigman with AI.