Inline the NotificationsLiveDataStoreRefactor flag

A first step to inline the NotificationsLiveDataStoreRefactor flag,
where each isEnabled() usages is replaced with a hardcoded `true`, and
I've let the IDE simplify the expressions.

This flag has been in nextfood since the last release. We've let it soak
longer on purpose.

Bug: 424001722
Test: smoke test the new NotificationLogger
Test: check lights out mode
Flag: EXEMPT mechanical refactor

Change-Id: I93874e9501a11a891189da611d8ec8a05560cd58