Reduce forward declarations in core/dom

Source/core/dom/TextLinkColors.h

 /*
  * 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, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
@@ skipping 16 matching lines @@
 
 #ifndef TextLinkColors_h
 #define TextLinkColors_h
 
 #include "platform/graphics/Color.h"
 #include "wtf/Noncopyable.h"
 
 namespace WebCore {
 
 class CSSPrimitiveValue;
-class Element;
 
 class TextLinkColors {
 WTF_MAKE_NONCOPYABLE(TextLinkColors);
 public:
     TextLinkColors();
 
     void setTextColor(const Color& color) { m_textColor = color; }
     Color textColor() const { return m_textColor; }
 
     const Color& linkColor() const { return m_linkColor; }
@@ skipping 10 matching lines @@
 
     Color m_textColor;
     Color m_linkColor;
     Color m_visitedLinkColor;
     Color m_activeLinkColor;
 };
 
 }
 
 #endif