Revert "[d8] cleanly force exit in d8 on windows."

src/d8-windows.cc

 // Copyright 2009 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.
 
 #include "src/d8.h"
 
 
 namespace v8 {
 
 
 void Shell::AddOSMethods(Isolate* isolate, Local<ObjectTemplate> os_templ) {}
 
-void Shell::Exit(int exit_code) {
-  // Use TerminateProcess avoid races between isolate threads and
-  // static destructors.
-  fflush(stdout);
-  fflush(stderr);
-  TerminateProcess(GetCurrentProcess(), exit_code);
-}
 
 }  // namespace v8