FWB: Peek notification time (1/2)

PS4: Make it work
PS5: no change
PS6: fix commit message
PS7: fix authorship

Change-Id: I7ce04b4d1123b6478a55d12c6be257aade2975e0

Conflicts:
	core/java/android/provider/Settings.java
	packages/SystemUI/src/com/android/systemui/statusbar/notification/NotificationPeek.java