Fix for gtest missing core classes, attempt 2

common_runtime_test loads both core-libart and
core-oj

Change-Id: I8a4d5750b99aed2e500cad89b841a57fe9c1ca69
diff --git a/runtime/dex_file_test.cc b/runtime/dex_file_test.cc
index d5304e7..b86a02e 100644
--- a/runtime/dex_file_test.cc
+++ b/runtime/dex_file_test.cc
@@ -205,7 +205,7 @@
   uint32_t checksum;
   ScopedObjectAccess soa(Thread::Current());
   std::string error_msg;
-  EXPECT_TRUE(DexFile::GetChecksum(GetLibCoreDexFileName().c_str(), &checksum, &error_msg))
+  EXPECT_TRUE(DexFile::GetChecksum(GetLibCoreDexFileNames()[0].c_str(), &checksum, &error_msg))
       << error_msg;
   EXPECT_EQ(java_lang_dex_file_->GetLocationChecksum(), checksum);
 }