Keystore2: Delete all super keys.

When a user was deleted, only the per boot key was deleted, but not the
lock screen bound wrapping keys. This patch makes sure that all user
specific super keys are deleted.

Added test for the behavior of unbind_keys_for_user with respect to
super keys.

Bug: 195924790
Test: keystore2_test

Merged-In: I3741450ddf971a6b4ee184fbc946cf127e1c39f8
Change-Id: I3741450ddf971a6b4ee184fbc946cf127e1c39f8
2 files changed