Add Statusbar Quick Peek [2/2]

Adds the ability to peek at the statusbar when hidden
by swiping down from the top edge of the screen.

Change-Id: Icd9591488b212f3a38c74c1efb2a7315af40c15c

Conflicts:
	core/java/android/provider/Settings.java
	packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBar.java