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

Source/core/css/StylePropertySet.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Research In Motion Limited. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. 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 20 matching lines @@
 #include "core/css/StyleSheetContents.h"
 #include "core/frame/UseCounter.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "wtf/text/StringBuilder.h"
 
 #ifndef NDEBUG
 #include "wtf/text/CString.h"
 #include <stdio.h>
 #endif
 
-using namespace std;
-
 namespace WebCore {
 
 static size_t sizeForImmutableStylePropertySetWithPropertyCount(unsigned count)
 {
     return sizeof(ImmutableStylePropertySet) - sizeof(void*) + sizeof(CSSValue*) * count + sizeof(StylePropertyMetadata) * count;
 }
 
 PassRefPtr<ImmutableStylePropertySet> ImmutableStylePropertySet::create(const CSSProperty* properties, unsigned count, CSSParserMode cssParserMode)
 {
     ASSERT(count <= MaxArraySize);
@@ skipping 560 matching lines @@
     result.appendLiteral(": ");
     result.append(propertyValue()->cssText());
     if (isImportant())
         result.appendLiteral(" !important");
     result.append(';');
     return result.toString();
 }
 
 
 } // namespace WebCore