Quicksettings: Immersive: Make last active state a system variable.

Will persist after reboot.

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>
Change-Id: I8f9f62d67e7de079e59ce5292604efacec042bcf

Conflicts:
	core/java/android/provider/Settings.java

Conflicts:
	core/java/android/provider/Settings.java
Switch quick settings drag to long click

PS2: Remove unused variables
PS3: Fix build

Change-Id: I441b7467127990f387d976132bffc8f881a55095

Conflicts:
	packages/SystemUI/src/com/android/systemui/statusbar/phone/QuickSettingsTileView.java