QuickSettings: fix missing GPS state

This will show the appropiate image when GPS got a fix.

PS2: use image set in the state object.
PS3: fix derp
PS4: it's too late - sorry
PS5: int ain't null

Change-Id: Id4055a9a811f42d411abaf740c7a6c8e8c240e9c
Signed-off-by: Dirk Rettschlag <dirk.rettschlag@gmail.com>

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