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

Source/core/rendering/svg/SVGTextMetrics.cpp

 /*
  * Copyright (C) Research In Motion Limited 2010-2012. 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 12 matching lines @@
 
 #include "core/rendering/svg/RenderSVGInlineText.h"
 #include "core/rendering/svg/SVGTextRunRenderingContext.h"
 
 namespace WebCore {
 
 SVGTextMetrics::SVGTextMetrics()
     : m_width(0)
     , m_height(0)
     , m_length(0)
+    , m_glyph(0)
 {
 }
 
 SVGTextMetrics::SVGTextMetrics(SVGTextMetrics::MetricsType)
     : m_width(0)
     , m_height(0)
     , m_length(1)
+    , m_glyph(0)
 {
 }
 
 SVGTextMetrics::SVGTextMetrics(RenderSVGInlineText* textRenderer, const TextRun& run)
 {
     ASSERT(textRenderer);
 
     float scalingFactor = textRenderer->scalingFactor();
     ASSERT(scalingFactor);
 
     const Font& scaledFont = textRenderer->scaledFont();
     int length = 0;
 
     // Calculate width/height using the scaled font, divide this result by the scalingFactor afterwards.
-    m_width = scaledFont.width(run, length, m_glyph.name) / scalingFactor;
+    m_width = scaledFont.width(run, length, m_glyph) / scalingFactor;
     m_height = scaledFont.fontMetrics().floatHeight() / scalingFactor;
 
-    m_glyph.unicodeString = run.is8Bit() ? String(run.characters8(), length) : String(run.characters16(), length);
-    m_glyph.isValid = true;
-
     ASSERT(length >= 0);
     m_length = static_cast<unsigned>(length);
 }
 
 TextRun SVGTextMetrics::constructTextRun(RenderSVGInlineText* text, unsigned position, unsigned length)
 {
     RenderStyle* style = text->style();
     ASSERT(style);
 
     TextRun run(static_cast<const LChar*>(0) // characters, will be set below if non-zero.
@@ skipping 24 matching lines @@
     ASSERT(run.charactersLength() >= run.length());
     return run;
 }
 
 SVGTextMetrics SVGTextMetrics::measureCharacterRange(RenderSVGInlineText* text, unsigned position, unsigned length)
 {
     ASSERT(text);
     return SVGTextMetrics(text, constructTextRun(text, position, length));
 }
 
-SVGTextMetrics::SVGTextMetrics(RenderSVGInlineText* text, unsigned position, unsigned length, float width, const String& glyphName)
+SVGTextMetrics::SVGTextMetrics(RenderSVGInlineText* text, unsigned position, unsigned length, float width, Glyph glyphNameGlyphId)
 {
     ASSERT(text);
 
     bool needsContext = textRunNeedsRenderingContext(text->style()->font());
     float scalingFactor = text->scalingFactor();
     ASSERT(scalingFactor);
 
     m_width = width / scalingFactor;
     m_height = text->scaledFont().fontMetrics().floatHeight() / scalingFactor;
-    if (needsContext) {
-        m_glyph.isValid = true;
-        m_glyph.unicodeString = text->substring(position, length);
-        m_glyph.name = glyphName;
-    }
+    m_glyph = needsContext ? glyphNameGlyphId : 0;
 
     m_length = length;
 }
 
 }