Change JIT code to use optimizing.

Obviously, will fall back to quick for most methods currently,
due to lack of -QUICK opcodes support.

Change-Id: I28882fbe805cd907275b6047437d9639a475964a
diff --git a/runtime/runtime.h b/runtime/runtime.h
index bcc7118..6fd1b07 100644
--- a/runtime/runtime.h
+++ b/runtime/runtime.h
@@ -552,6 +552,8 @@
     return method_ref_string_init_reg_map_;
   }
 
+  bool IsDebuggable() const;
+
  private:
   static void InitPlatformSignalHandlers();