@hide new setting and move it to appropriate place.
SystemUI: Remove the dark pixel artifacts from the back arrow drawable

The arrow had some mostly transparent pixels that made it look
kind of like the device had defective pixels. Found by Cyril Mottier.

Change-Id: Ia78453868ebe7e3291d01c96b9beafc78ea3cdcc

Conflicts:

	packages/SystemUI/res/drawable-xhdpi/ic_sysbar_back_land.png
PackageManager: Restrict system packages to protected storage

Don't allow packages signed with the platform key to be
installed into user (or app) controlled storage

Change-Id: I7390b3bdf5289411f7a335c69635bed9f74bbfb3
Framework: Enable multi-user support for Notification light

Change-Id: I4fb84fdb0c9e1592c2a421011c303a789cde8c8c