Revert "Remove junit from our core image."

To put us back green. Will re-land when vogar is cleaned up.

This reverts commit 0ad65a3c794b18101def5096d8ed151382c9d5aa.

Change-Id: I24a58bd87f133132d7774104eb8f77d6bbd6292b
diff --git a/build/Android.common_path.mk b/build/Android.common_path.mk
index 2d6b6a3..e0c0b0c 100644
--- a/build/Android.common_path.mk
+++ b/build/Android.common_path.mk
@@ -80,7 +80,7 @@
 TARGET_CORE_IMG_LOCATION := $(ART_TARGET_TEST_OUT)/core.art
 
 # Jar files for core.art.
-TARGET_CORE_JARS := core-libart conscrypt okhttp bouncycastle
+TARGET_CORE_JARS := core-libart conscrypt okhttp core-junit bouncycastle
 HOST_CORE_JARS := $(addsuffix -hostdex,$(TARGET_CORE_JARS))
 
 HOST_CORE_DEX_LOCATIONS   := $(foreach jar,$(HOST_CORE_JARS),  $(HOST_OUT_JAVA_LIBRARIES)/$(jar).jar)
diff --git a/tools/run-jdwp-tests.sh b/tools/run-jdwp-tests.sh
index 77e8004..17c4556 100755
--- a/tools/run-jdwp-tests.sh
+++ b/tools/run-jdwp-tests.sh
@@ -22,7 +22,7 @@
 # Jar containing all the tests.
 test_jar=out/host/linux-x86/framework/apache-harmony-jdwp-tests-hostdex.jar
 
-if [ ! -f $test_jar ]; then
+if [ ! -f $test_jar -o ! -f $junit_jar ]; then
   echo "Before running, you must build jdwp tests and vogar:" \
        "make apache-harmony-jdwp-tests-hostdex vogar vogar.jar"
   exit 1