Zhonya's healing bug

At low health, pop zhonya's item ability with no healing perks and still get health. Even blocks damage before zhonya's item ability cast making abilities and autos do the damage and disappear int the champion (on hit) while doing no damage. This implementation is flawed as per the definition of zhonya's item ability as instant.

Which come first, damage, animation, or ability animation which cancels damage. This is the usual order yet Zhonya's item ability rearranges this chain. This is not the correct implementation.