The current implementation of OATHUserRepository::persist() causes every
key to get a new ID when it's saved. This, combined with ::removeKey()
which compares keys by ID, means that using recovery codes to disable
TOTP is broken since TOTPKey calls persist() to mark the code as saved
just before the key is deleted.
In this patch I've chosen to add a new ::updateKey() method instead of
fixing ::persist(). This is more in line with the other new APIs in
OATHUserRepository (namely ::createKey() and ::removeKey()), and is
something I've been planning to do eventually - this bug just made that
a bit more urgent. ::persist() should be dropped once WebAuthn has been
updated too.
Tests are also updated - OATHUserRepositoryTest now updates the key
before deleting it and there's a new TOTPDisableFormTest to test the
entire disabling process.
Bug: T363548
Change-Id: I86ddc8e5bfc9cf74c587ffdff523f559c5a3c08c
