Make __proto__ a foreign callback on Object.prototype.

test/cctest/test-api.cc

 // Copyright 2012 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 1831 matching lines @@
       CheckThisNamedPropertyHandler,
       CheckThisNamedPropertySetter,
       CheckThisNamedPropertyQuery,
       CheckThisNamedPropertyDeleter,
       CheckThisNamedPropertyEnumerator);
 
   bottom = templ->GetFunction()->NewInstance();
   Local<v8::Object> top = templ->GetFunction()->NewInstance();
   Local<v8::Object> middle = templ->GetFunction()->NewInstance();
 
-  bottom->Set(v8_str("__proto__"), middle);
-  middle->Set(v8_str("__proto__"), top);
+  bottom->SetPrototype(middle);
+  middle->SetPrototype(top);
   env->Global()->Set(v8_str("obj"), bottom);
 
   // Indexed and named get.
   Script::Compile(v8_str("obj[0]"))->Run();
   Script::Compile(v8_str("obj.x"))->Run();
 
   // Indexed and named set.
   Script::Compile(v8_str("obj[1] = 42"))->Run();
   Script::Compile(v8_str("obj.y = 42"))->Run();
 
@@ skipping 7779 matching lines @@
 // is invoked
 THREADED_TEST(InterceptorCallICCacheableNotNeeded) {
   v8::HandleScope scope;
   v8::Handle<v8::ObjectTemplate> templ = ObjectTemplate::New();
   templ->SetNamedPropertyHandler(InterceptorCallICGetter4);
   LocalContext context;
   context->Global()->Set(v8_str("o"), templ->NewInstance());
   call_ic_function4 =
       v8_compile("function f(x) { return x - 1; }; f")->Run();
   v8::Handle<Value> value = CompileRun(
-    "o.__proto__.x = function(x) { return x + 1; };"
+    "Object.getPrototypeOf(o).x = function(x) { return x + 1; };"
     "var result = 0;"
     "for (var i = 0; i < 1000; i++) {"
     "  result = o.x(42);"
     "}");
   CHECK_EQ(41, value->Int32Value());
 }
 
 
 // Test the case when we stored cacheable lookup into
 // a stub, but it got invalidated later on
@@ skipping 8548 matching lines @@
   i::Semaphore* sem_;
   volatile int sem_value_;
 };
 
 
 THREADED_TEST(SemaphoreInterruption) {
   ThreadInterruptTest().RunTest();
 }
 
 #endif  // WIN32