Moving junit out of core.jar and into core-junit.jar.

Also extending the arbitrary limit on build argument sizes,
which I ran up against in building after this change.

Change-Id: Iba79a37b27e7d5efa2b02a99aa253a2eec7ede75
diff --git a/core/java.mk b/core/java.mk
index 11b615f..62ae7a4 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -29,7 +29,7 @@
   endif
 else
   ifneq ($(LOCAL_NO_STANDARD_LIBRARIES),true)
-    LOCAL_JAVA_LIBRARIES := core ext framework $(LOCAL_JAVA_LIBRARIES)
+    LOCAL_JAVA_LIBRARIES := core core-junit ext framework $(LOCAL_JAVA_LIBRARIES)
   endif
 endif
 LOCAL_JAVA_LIBRARIES := $(sort $(LOCAL_JAVA_LIBRARIES))