Remove tabStop feature

Source/core/dom/ElementRareData.h

 /*
  * Copyright (C) 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2008 David Smith <catfish.man@gmail.com>
  *
  * 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,
@@ skipping 47 matching lines @@
         m_tabindex = index;
         setElementFlag(TabIndexWasSetExplicitly, true);
     }
 
     void clearTabIndexExplicitly()
     {
         m_tabindex = 0;
         clearElementFlag(TabIndexWasSetExplicitly);
     }
 
-    bool tabStop() const { return m_tabStop; }
-
-    void setTabStop(bool flag) { m_tabStop = flag; }
-
     CSSStyleDeclaration& ensureInlineCSSStyleDeclaration(Element* ownerElement);
 
     void clearShadow() { m_shadow = nullptr; }
     ElementShadow* shadow() const { return m_shadow.get(); }
     ElementShadow& ensureShadow()
     {
         if (!m_shadow)
             m_shadow = ElementShadow::create();
         return *m_shadow;
     }
@@ skipping 44 matching lines @@
     CustomElementDefinition* customElementDefinition() const { return m_customElementDefinition.get(); }
 
     AttrNodeList& ensureAttrNodeList();
     AttrNodeList* attrNodeList() { return m_attrNodeList.get(); }
     void removeAttrNodeList() { m_attrNodeList.clear(); }
 
     DECLARE_TRACE_AFTER_DISPATCH();
 
 private:
     short m_tabindex;
-    unsigned short m_tabStop : 1;
     unsigned short m_proxyCount : 10;
 
     LayoutSize m_minimumSizeForResizing;
     IntSize m_savedLayerScrollOffset;
 
     OwnPtrWillBeMember<DatasetDOMStringMap> m_dataset;
     OwnPtrWillBeMember<ClassList> m_classList;
     OwnPtrWillBeMember<ElementShadow> m_shadow;
     OwnPtrWillBeMember<NamedNodeMap> m_attributeMap;
     OwnPtrWillBeMember<AttrNodeList> m_attrNodeList;
@@ skipping 12 matching lines @@
 };
 
 inline LayoutSize defaultMinimumSizeForResizing()
 {
     return LayoutSize(LayoutUnit::max(), LayoutUnit::max());
 }
 
 inline ElementRareData::ElementRareData(LayoutObject* layoutObject)
     : NodeRareData(layoutObject)
     , m_tabindex(0)
-    , m_tabStop(true)
     , m_proxyCount(0)
     , m_minimumSizeForResizing(defaultMinimumSizeForResizing())
 {
     m_isElementRareData = true;
 }
 
 inline ElementRareData::~ElementRareData()
 {
 #if !ENABLE(OILPAN)
     ASSERT(!m_shadow);
@@ skipping 57 matching lines @@
     case FIRST_LETTER:
         return m_generatedFirstLetter.get();
     default:
         return 0;
     }
 }
 
 } // namespace
 
 #endif // ElementRareData_h