Add verification of boot.oat generated on device

Change-Id: I069586205a9a92fc7375ccf5cdde136bbbcfc800
diff --git a/runtime/class_linker.h b/runtime/class_linker.h
index df33672..df1ecc6 100644
--- a/runtime/class_linker.h
+++ b/runtime/class_linker.h
@@ -359,7 +359,7 @@
 
   // Initialize class linker from one or more images.
   void InitFromImage() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
-  OatFile* OpenOat(const gc::space::ImageSpace* space)
+  OatFile& GetImageOatFile(gc::space::ImageSpace* space)
       LOCKS_EXCLUDED(dex_lock_)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   static void InitFromImageCallback(mirror::Object* obj, void* arg)