Settings: Port notification drawer custom background (1/2)

Change-Id: If7da7fc82942ea74c46cabd48e0ee874f4c20f0a

Conflicts:
	AndroidManifest.xml
	res/layout/slider_preference.xml
	res/values/arrays.xml
	res/values/strings.xml
	res/xml/notification_drawer_settings.xml
	src/com/android/settings/widget/SeekBarPreference.java