Backward-compat for DashboardCategory with app use old keys

- Detect whether an app is using old key, new key, or a mix of both.
-- If app is using new keys, skip. They are already in the new IA.
-- If app is using old/new keys mixed, skip. Using both type of keys
   implies the app wants to support old/new platform.
-- If app is using old keys only, map their tiles to new categories.

Bug: 32382487
Test: new unit tests
Change-Id: I3bbd09c531a97801dc382661a8bb10d0391bc177