Framework: Notification drawer wallpaper picker with alpha slider (1/2)

Conflicts:

	packages/SystemUI/res/drawable-hdpi/notification_panel_bg.9.png
	packages/SystemUI/res/drawable-sw600dp-hdpi/notification_panel_bg.9.png
	packages/SystemUI/res/drawable-xhdpi/notification_panel_bg.9.png
different than chris