Inform Jack of the min sdk

Set Jack min sdk according to LOCAL_SDK_VERSION. Gives Jack current
version when LOCAL_SDK_VERSION is not available.

Bug: 27371864

Change-Id: I5db233fe09aed0fae37fe9a92658bc8f24b86cdf
diff --git a/core/prebuilt_internal.mk b/core/prebuilt_internal.mk
index f9ec7d5..fb9cf8d 100644
--- a/core/prebuilt_internal.mk
+++ b/core/prebuilt_internal.mk
@@ -339,6 +339,7 @@
 
 # We may be building classes.jack from a host jar for host dalvik Java library.
 $(intermediates.COMMON)/classes.jack : PRIVATE_JACK_FLAGS:=$(LOCAL_JACK_FLAGS)
+$(intermediates.COMMON)/classes.jack : PRIVATE_JACK_MIN_SDK_VERSION := 1
 $(intermediates.COMMON)/classes.jack : $(my_src_jar) \
         $(LOCAL_ADDITIONAL_DEPENDENCIES) $(JACK) | setup-jack-server
 	$(transform-jar-to-jack)