Remove unneeded 'using namespace std'.

Source/core/page/Chrome.cpp

 /*
  * Copyright (C) 2006, 2007, 2009, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2012, Samsung Electronics. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 28 matching lines @@
 #include "platform/DateTimeChooser.h"
 #include "platform/FileChooser.h"
 #include "platform/geometry/FloatRect.h"
 #include "platform/network/DNS.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/Vector.h"
 
 namespace WebCore {
 
 using namespace HTMLNames;
-using namespace std;
 
 Chrome::Chrome(Page* page, ChromeClient* client)
     : m_page(page)
     , m_client(client)
 {
     ASSERT(m_client);
 }
 
 Chrome::~Chrome()
 {
@@ skipping 353 matching lines @@
 }
 
 void Chrome::notifyPopupOpeningObservers() const
 {
     const Vector<PopupOpeningObserver*> observers(m_popupOpeningObservers);
     for (size_t i = 0; i < observers.size(); ++i)
         observers[i]->willOpenPopup();
 }
 
 } // namespace WebCore