Allow seconday label to be off in new tiles

Introduce a new state type called AdapterState. The goal of the
AdapterState is to do everything BooleanState did, except for
overwriting the empty seconday label with default text on/off.

Fixes: 322204517
Flag: aconfig com.android.systemui.qs_new_tiles DEVELOPMENT
Test: Manual. When the flag is on, stateless tiles such as Font should
not have a secondary label, and their label should be vertically
centered.

Change-Id: I9d13874bf2dcf52f33696ae28e648c4f6bfe35eb