Fix logic error in assert in IsUndeclaredGlobal()

src/proxy.js

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 54 matching lines @@
   return %CreateJSFunctionProxy(
     handler, callTrap, constructTrap, $Function.prototype)
 }
 
 
 // -------------------------------------------------------------------
 
 function SetUpProxy() {
   %CheckIsBootstrapping()
 
-  global.Proxy = $Proxy;
+  var global_receiver = %GlobalReceiver(global);
+  global_receiver.Proxy = $Proxy;
 
   // Set up non-enumerable properties of the Proxy object.
   InstallFunctions($Proxy, DONT_ENUM, [
     "create", ProxyCreate,
     "createFunction", ProxyCreateFunction
   ])
 }
 
 SetUpProxy();
 
@@ skipping 118 matching lines @@
 }
 
 function ProxyEnumerate(proxy) {
   var handler = %GetHandler(proxy)
   if (IS_UNDEFINED(handler.enumerate)) {
     return %Apply(DerivedEnumerateTrap, handler, [], 0, 0)
   } else {
     return ToNameArray(handler.enumerate(), "enumerate", false)
   }
 }