Track notifications hidden time

Adds tracking for two actions:
* ACTION_NOTIFICATIONS_HIDDEN_FOR_MEASURE
  tracks time notifications spent in 'hidden' state
* ACTION_NOTIFICATIONS_HIDDEN_FOR_MEASURE_WITH_SHADE_OPEN
  tracks time notifications spent in 'hidden' state when
  otherwise they should be visible

Bug: 318342273
Test: atest DisplaySwitchNotificationsHiderTrackerTest
Test: manually check that LatencyTracker is invoked
  when notifications are hidden
Flag: ACONFIG notifications_hide_on_display_switch DISABLED
Change-Id: I847cc8959247ce41822f719f18fa910b3427f747