Use glyph-ids for lookups of SVG font kerning-pairs

Source/core/rendering/svg/SVGTextLayoutEngineSpacing.h

 /*
  * Copyright (C) Research In Motion Limited 2010. 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,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 16 matching lines @@
 class Font;
 class SVGRenderStyle;
 class SVGElement;
 
 // Helper class used by SVGTextLayoutEngine to handle 'kerning' / 'letter-spacing' and 'word-spacing'.
 class SVGTextLayoutEngineSpacing {
     WTF_MAKE_NONCOPYABLE(SVGTextLayoutEngineSpacing);
 public:
     SVGTextLayoutEngineSpacing(const Font&);
 
-    float calculateSVGKerning(bool isVerticalText, const SVGTextMetrics::Glyph& currentGlyph);
+    float calculateSVGKerning(bool isVerticalText, Glyph currentGlyph);
     float calculateCSSKerningAndSpacing(const SVGRenderStyle*, SVGElement* lengthContext, UChar currentCharacter);
 
 private:
     const Font& m_font;
     UChar m_lastCharacter;
 
 #if ENABLE(SVG_FONTS)
-    SVGTextMetrics::Glyph m_lastGlyph;
+    Glyph m_lastGlyph;
 #endif
 };
 
 } // namespace WebCore
 
 #endif