[Gameplay] Black Shield - Recieving Physical Damage under Friendly Tower does not Aggro Enemies

Steps:

1. Black Shield yourself
2. Stand under friendly tower
3. Have an enemy attack you (while the turret is aggroed on minions)

Result: The turret will not aggro the champion damaging you

Notes: Specifically this happened with Morgana under the tower, an enemy Vi attacking her. Both autoing and using her Empowered E, the tower would not aggro until the shield dropped. The Vi asked in all chat what had happened, so it was two factor confirmed.