Add an abstraction over a compiled code.

That's just step 1, moving code-related functions of ArtMethod to
another class. That class is only a wrapper on an ArtMethod, but will
be changed to be a wrapper around compiled code.

Change-Id: I6f35fc06d37220558dff61691e51ae20066b0dd6
diff --git a/runtime/oat_file.h b/runtime/oat_file.h
index 27f8677..364b734 100644
--- a/runtime/oat_file.h
+++ b/runtime/oat_file.h
@@ -29,6 +29,7 @@
 #include "mirror/class.h"
 #include "oat.h"
 #include "os.h"
+#include "utils.h"
 
 namespace art {