Add --image-classes to dex2oat

Change-Id: Ia88f9d302e0f9cd72be2199ee46d212d99864c67
diff --git a/src/image_test.cc b/src/image_test.cc
index 812b281..6901482 100644
--- a/src/image_test.cc
+++ b/src/image_test.cc
@@ -29,7 +29,7 @@
     EXPECT_TRUE(klass != NULL) << descriptor;
   }
 
-  ImageWriter writer;
+  ImageWriter writer(NULL);
   ScratchFile tmp_image;
   const uintptr_t requested_image_base = 0x60000000;
   bool success_image = writer.Write(tmp_image.GetFilename(), requested_image_base,