Convert sysui to bp

Test: tests gonna test, builds gonna build
Change-Id: I7f1ef2e82ce2c74253c57de8d73079dcfe2d2264
diff --git a/packages/CarSystemUI/proguard.flags b/packages/CarSystemUI/proguard.flags
index ceb037c..a81c7e0 100644
--- a/packages/CarSystemUI/proguard.flags
+++ b/packages/CarSystemUI/proguard.flags
@@ -1 +1,3 @@
 -keep class com.android.systemui.CarSystemUIFactory
+
+-include ../SystemUI/proguard.flags