Add jack's argument files to prerequisites

Dex files should be updated when jack-default.args or
proguard*.flags are modified.

Bug: 27954979
Change-Id: I72a7084302f4ef92a89a8068f03f790dd7acd582
diff --git a/core/config.mk b/core/config.mk
index 8ac1d50..6df4430 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -546,9 +546,11 @@
 JARJAR := $(HOST_OUT_JAVA_LIBRARIES)/jarjar.jar
 
 ifneq ($(ANDROID_JACK_EXTRA_ARGS),)
+JACK_DEFAULT_ARGS :=
 DEFAULT_JACK_EXTRA_ARGS := $(ANDROID_JACK_EXTRA_ARGS)
 else
-DEFAULT_JACK_EXTRA_ARGS := @$(BUILD_SYSTEM)/jack-default.args
+JACK_DEFAULT_ARGS := $(BUILD_SYSTEM)/jack-default.args
+DEFAULT_JACK_EXTRA_ARGS := @$(JACK_DEFAULT_ARGS)
 endif
 # Turn off jack warnings by default.
 DEFAULT_JACK_EXTRA_ARGS += --verbose error