Remove unused includes from core/html .cpp files

Source/core/html/HTMLPreElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 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 Public
  * License as published by the Free Software Foundation; either
  * 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 "config.h"
 #include "core/html/HTMLPreElement.h"
 
 #include "CSSPropertyNames.h"
 #include "CSSValueKeywords.h"
 #include "HTMLNames.h"
 #include "core/css/StylePropertySet.h"
-#include "core/dom/Attribute.h"
 
 namespace WebCore {
 
 using namespace HTMLNames;
 
 inline HTMLPreElement::HTMLPreElement(const QualifiedName& tagName, Document* document)
     : HTMLElement(tagName, document)
 {
     ScriptWrappable::init(this);
 }
@@ skipping 12 matching lines @@
 
 void HTMLPreElement::collectStyleForPresentationAttribute(const QualifiedName& name, const AtomicString& value, MutableStylePropertySet* style)
 {
     if (name == wrapAttr)
         style->setProperty(CSSPropertyWhiteSpace, CSSValuePreWrap);
     else
         HTMLElement::collectStyleForPresentationAttribute(name, value, style);
 }
 
 }