Rename setShouldExtendLifetime in LifetimeExtender

Rename NotificationLifetimeExtender.setShouldExtendLifetime to
setShouldManageLifetime.  This is more clear in what the logic actually
is and reads better.

Test: runtest systemui
Change-Id: Ic5792322ef0a557812d58f07285acee32cce0c1a
9 files changed