Introduce data usage table for per-method ranking.

- have a hidden table for per-method promotion
- make filter API use it (phone, email only)
- add a unit test
- remove an old test using previous API

Must be after: I602c0b83afca674904946f59bbdfc4dca07d46e4

Bug: 4371572
Change-Id: I82052953d5dad42ac171df29248ed25e9b4a2434
3 files changed