Remove some unnecessary using namespaces and add include guards

third_party/WebKit/Source/core/layout/LayoutSlider.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Publicw
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */
 
 #include "core/layout/LayoutSlider.h"
 
 #include "core/InputTypeNames.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/html/HTMLInputElement.h"
 #include "core/html/shadow/ShadowElementNames.h"
 #include "core/html/shadow/SliderThumbElement.h"
 #include "core/layout/LayoutSliderThumb.h"
 #include "wtf/MathExtras.h"
 
-using namespace ::std;
-
 namespace blink {
 
 const int LayoutSlider::defaultTrackLength = 129;
 
 LayoutSlider::LayoutSlider(HTMLInputElement* element)
     : LayoutFlexibleBox(element) {
   // We assume LayoutSlider works only with <input type=range>.
   ASSERT(element->type() == InputTypeNames::range);
 }
 
@@ skipping 30 matching lines @@
     toLayoutSliderThumb(thumbBox)->updateAppearance(styleRef());
 
   LayoutFlexibleBox::layout();
 }
 
 bool LayoutSlider::inDragMode() const {
   return sliderThumbElement()->isActive();
 }
 
 }  // namespace blink