ART: Move RegisterNatives helper

Move the helper closer to the users.

Test: m test-art-host
Change-Id: Id05ce5f60af54d0c5aef0c7d8932706c4602fc94
diff --git a/runtime/native/java_lang_VMClassLoader.cc b/runtime/native/java_lang_VMClassLoader.cc
index 55955e7..fc50d55 100644
--- a/runtime/native/java_lang_VMClassLoader.cc
+++ b/runtime/native/java_lang_VMClassLoader.cc
@@ -22,6 +22,7 @@
 #include "jni_internal.h"
 #include "mirror/class_loader.h"
 #include "mirror/object-inl.h"
+#include "native_util.h"
 #include "obj_ptr.h"
 #include "scoped_fast_native_object_access-inl.h"
 #include "ScopedLocalRef.h"