Replace core-junit with legacy-test

m -j32 checkbuild cts droid
adb reboot bootloader
fastboot flashall -w
cts-tradefed run cts -m CtsLibcoreTestCases

Bug: 30188076
Test: As above
Change-Id: I2d49cb3c451cb265d026f9a700a61b3fc0d2ed82
diff --git a/core/config.mk b/core/config.mk
index 677d210..f9d6e7e 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -696,7 +696,7 @@
 
 # allow overriding default Java libraries on a per-target basis
 ifeq ($(TARGET_DEFAULT_JAVA_LIBRARIES),)
-  TARGET_DEFAULT_JAVA_LIBRARIES := core-oj core-libart core-junit ext framework okhttp
+  TARGET_DEFAULT_JAVA_LIBRARIES := core-oj core-libart legacy-test ext framework okhttp
 endif
 
 # Flags for DEX2OAT