Support 'extend-to-zoom' viewport descriptor value

Source/core/platform/Length.h

 /*
     Copyright (C) 1999 Lars Knoll (knoll@kde.org)
     Copyright (C) 2006, 2008 Apple Inc. All rights reserved.
     Copyright (C) 2011 Rik Cabanier (cabanier@adobe.com)
     Copyright (C) 2011 Adobe Systems Incorporated. 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 22 matching lines @@
 #include "wtf/Vector.h"
 
 namespace WebCore {
 
 enum LengthType {
     Auto, Relative, Percent, Fixed,
     Intrinsic, MinIntrinsic,
     MinContent, MaxContent, FillAvailable, FitContent,
     Calculated,
     ViewportPercentageWidth, ViewportPercentageHeight, ViewportPercentageMin, ViewportPercentageMax,
+    ExtendToZoom,
     Undefined
 };
 
 class CalculationValue;
 
 struct Length {
     WTF_MAKE_FAST_ALLOCATED;
 public:
     Length()
         :  m_intValue(0), m_quirk(false), m_type(Auto), m_isFloat(false)
@@ skipping 257 matching lines @@
     bool m_quirk;
     unsigned char m_type;
     bool m_isFloat;
 };
 
 Vector<Length> parseHTMLAreaElementCoords(const String&);
 
 } // namespace WebCore
 
 #endif // Length_h