System UI for auto.

This change adds in the beginnings of System UI for
the automotive use case. We extend the Phone status
and navigation bar and override the parts which are
customized for auto.

The navigation bar itself is built from a resource
array specified in car_arrays.xml to allow of ease
of customization of the shortcuts that are in the
navigation bar.

Bug: 26301185
Change-Id: I780a2ef9dd5ae2a4be9355b5874d08f521a86fa7
diff --git a/packages/SystemUI/proguard.flags b/packages/SystemUI/proguard.flags
index 6a10c2c..bc18221 100644
--- a/packages/SystemUI/proguard.flags
+++ b/packages/SystemUI/proguard.flags
@@ -10,6 +10,7 @@
   public void setGlowScale(float);
 }
 
+-keep class com.android.systemui.statusbar.car.CarStatusBar
 -keep class com.android.systemui.statusbar.phone.PhoneStatusBar
 -keep class com.android.systemui.statusbar.tv.TvStatusBar