Make the server side to support both 1 consent and 3 consents.

- This will support both upgrade and downgrade (rollback).

The logic to handle Upgrade (1 consent -> 3 consents) and
Downgrade/Rollack (3 consents -> 1 consent)

1) On upgrade from 1 consent to 3 consents.
We assume the following logic:
1.a) if 1 consent is GIVEN, then we will upgrade to 3 GIVEN consents.
1.b) Otherwise we will upgrade to 3 REVOKED consents.

2) On downgrade (aka. rollback) from 3 consents to 1 consent.
We assume the following logic:
2.a) if all 3 consents are GIVEN, then we will downgrade to 1 GIVEN
consent.
2.b) Otherwise we will downgrade to 1 REVOKED consent.
Note: in this case, we could lose some consents here. For example if we
have 2 GIVENs and 1 REVOKED, we will downgrade to 1 REVOKED, losing 2
GIVENs.

Bug: b/258678530
Test: presubmit
Change-Id: Ibb182359d327b309c906c4049ebae21e5e623e93