Use boot image for all tests instead of core.art.

Test: m test-art-host-gtest
Test: test.py -b -r --host --optimizing
Test: mmma art/tools/ahat
Test: (the tests above do not build core.art)
Bug: 147817558
Bug: 147819342
Change-Id: I412fa140e78fd3769696a6635b896b1cf975edd6
diff --git a/tools/run-libcore-tests.sh b/tools/run-libcore-tests.sh
index ff3c433..c6731b5 100755
--- a/tools/run-libcore-tests.sh
+++ b/tools/run-libcore-tests.sh
@@ -184,7 +184,7 @@
   case "$1" in
     --mode=device)
       vogar_args="$vogar_args --mode=device"
-      vogar_args="$vogar_args --vm-arg -Ximage:/data/art-test/core.art"
+      vogar_args="$vogar_args --vm-arg -Ximage:/apex/com.android.art/javalib/boot.art"
       vogar_args="$vogar_args $(boot_classpath_arg /apex/com.android.art/javalib $BOOT_CLASSPATH_JARS)"
       execution_mode="device"
       ;;