Refactor NotificationEntry utility methods

IDE extraction of notification visiblity methods into NotificationEntry

Bug: 324111564
Flag: N/A -- IDE tooling refactor only
Test: atest NotificationEntryTest
Test: atest NotificationLockscreenUserManagerTest
Change-Id: Ieaae2f9caf778f7ca90056bc7174fddc878a956d
3 files changed