Mobs are supposed to pick up player dropped armor/tools/weapons

One of the changes with the addition of the despawning mechanics is ways in which mobs can persist, mobs are supposed to pick up player dropped armor, weapons, and tools now, and picking these up is supposed to cause the mob to persist (not despawn) When dropping armor, weapons, and tools onto the ground for zombies that have naturally spawned into the world to pick up, they would not pick up these items and ignored them.