Revert "PEEK [1/2]"

This reverts commit 9595b1d94e9d09e4876f5bbd507b4740cd7b056f.

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