Use plain int for borders widths when possible

Source/core/style/BorderValue.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Graham Dennis (graham.dennis@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
@@ skipping 68 matching lines @@
     }
 
     void setColor(const StyleColor& color)
     {
         m_color = color.resolve(Color());
         m_colorIsCurrentColor = color.isCurrentColor();
     }
 
     StyleColor color() const { return m_colorIsCurrentColor ? StyleColor::currentColor() : StyleColor(m_color); }
 
-    unsigned width() const { return m_width; }
+    int width() const { return m_width; }
 
     EBorderStyle style() const { return static_cast<EBorderStyle>(m_style); }
     void setStyle(EBorderStyle style) { m_style = style; }
 
 protected:
     Color m_color;
     unsigned m_colorIsCurrentColor : 1;
 
     unsigned m_width : 26;
     unsigned m_style : 4; // EBorderStyle
 
     // This is only used by OutlineValue but moved here to keep the bits packed.
     unsigned m_isAuto : 1; // OutlineIsAuto
 };
 
 } // namespace blink
 
 #endif // BorderValue_h