Incremental local builds for frameworks

Change-Id: I810652adf4359f7eb0b87adc4f5ed45da5429e6a
diff --git a/Android.mk b/Android.mk
index c3e679b..a323dca 100644
--- a/Android.mk
+++ b/Android.mk
@@ -1193,6 +1193,11 @@
 
 LOCAL_DX_FLAGS := --core-library
 
+ifneq ($(INCREMENTAL_BUILDS),)
+    LOCAL_PROGUARD_ENABLED := disabled
+    LOCAL_JACK_ENABLED := incremental
+endif
+
 include $(BUILD_JAVA_LIBRARY)