HALO colors: a lil improvement

Shouldn't break themeability this time, the custom colors has it's own halo bg

Signed-off-by: Kristofer Ard <kristoferard@gmail.com>

Change-Id: Icfbdfa2e0f44527a80f1e9365a243a654c61a9a2

Conflicts:
	packages/SystemUI/res/values/colors.xml