New parser mode for CSSOM @viewport descriptors.

Source/core/css/StylePropertySet.h

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2008, 2012 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,
@@ skipping 118 matching lines @@
         , m_isMutable(true)
         , m_arraySize(0)
     { }
 
     StylePropertySet(CSSParserMode cssParserMode, unsigned immutableArraySize)
         : m_cssParserMode(cssParserMode)
         , m_isMutable(false)
         , m_arraySize(immutableArraySize)
     { }
 
-    unsigned m_cssParserMode : 2;
+    unsigned m_cssParserMode : 3;
     mutable unsigned m_isMutable : 1;
-    unsigned m_arraySize : 29;
+    unsigned m_arraySize : 28;

[eseidel, 2013/09/10 16:33:58]

Do we have a constant somewhere to help make sure we never overflow this?

[rune, 2013/09/12 13:05:01]

Done.

 
     friend class PropertySetCSSStyleDeclaration;
 };
 
 class ImmutableStylePropertySet : public StylePropertySet {
 public:
     ~ImmutableStylePropertySet();
     static PassRefPtr<ImmutableStylePropertySet> create(const CSSProperty* properties, unsigned count, CSSParserMode);
 
     unsigned propertyCount() const { return m_arraySize; }
@@ skipping 104 matching lines @@
 
     if (m_isMutable)
         delete static_cast<MutableStylePropertySet*>(this);
     else
         delete static_cast<ImmutableStylePropertySet*>(this);
 }
 
 } // namespace WebCore
 
 #endif // StylePropertySet_h