Removing "using" declarations that import names in the C++ Standard library.

Source/core/dom/Document.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) Research In Motion Limited 2010-2011. All rights reserved.
@@ skipping 180 matching lines @@
 #include "platform/weborigin/SecurityOrigin.h"
 #include "public/platform/Platform.h"
 #include "wtf/CurrentTime.h"
 #include "wtf/HashFunctions.h"
 #include "wtf/MainThread.h"
 #include "wtf/StdLibExtras.h"
 #include "wtf/TemporaryChange.h"
 #include "wtf/text/StringBuffer.h"
 #include "wtf/text/TextEncodingRegistry.h"
 
-using namespace std;
 using namespace WTF;
 using namespace Unicode;
 
 namespace WebCore {
 
 using namespace HTMLNames;
 
 static const unsigned cMaxWriteRecursionDepth = 21;
 
 // This amount of time must have elapsed before we will even consider scheduling a layout without a delay.
@@ skipping 5626 matching lines @@
     visitor->trace(m_compositorPendingAnimations);
     visitor->trace(m_contextDocument);
     visitor->registerWeakMembers<Document, &Document::clearWeakMembers>(this);
     DocumentSupplementable::trace(visitor);
     TreeScope::trace(visitor);
     ContainerNode::trace(visitor);
     ExecutionContext::trace(visitor);
 }
 
 } // namespace WebCore