Wrap runtime.js in a function.

src/object-observe.js

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 var $observeNotifyChange;
 var $observeEnqueueSpliceRecord;
 var $observeBeginPerformSplice;
 var $observeEndPerformSplice;
 var $observeNativeObjectObserve;
 var $observeNativeObjectGetNotifier;
@@ skipping 299 matching lines @@
 }
 
 
 function ConvertAcceptListToTypeMap(arg) {
   // We use undefined as a sentinel for the default accept list.
   if (IS_UNDEFINED(arg))
     return arg;
 
   if (!IS_SPEC_OBJECT(arg)) throw MakeTypeError(kObserveInvalidAccept);
 
-  var len = ToInteger(arg.length);
+  var len = $toInteger(arg.length);
   if (len < 0) len = 0;
 
   return TypeMapCreateFromList(arg, len);
 }
 
 
 // CallbackInfo's optimized state is just a number which represents its global
 // priority. When a change record must be enqueued for the callback, it
 // normalizes. When delivery clears any pending change records, it re-optimizes.
 function CallbackInfoGet(callback) {
@@ skipping 347 matching lines @@
 
 $observeNotifyChange = NotifyChange;
 $observeEnqueueSpliceRecord = EnqueueSpliceRecord;
 $observeBeginPerformSplice = BeginPerformSplice;
 $observeEndPerformSplice = EndPerformSplice;
 $observeNativeObjectObserve = NativeObjectObserve;
 $observeNativeObjectGetNotifier = NativeObjectGetNotifier;
 $observeNativeObjectNotifierPerformChange = NativeObjectNotifierPerformChange;
 
 })();