Use PreparationCoordinator to inflate notifs

In the (old/current) notification pipeline, NotificationEntryManager
handles inflating views.  In the NewNotifPipeline, PreparationCoordinator
will trigger inflation via a NotifInflater and will keep track
of what is/isn't inflated.

If a notification isn't done inflating, then the PreparationCoordinator
will filter it from the NotifListBuilder.

Test: atest SystemUiTests
Change-Id: I7a5c01041312ff179e8c723f66207b3bd042c857