Improve shaping segmentation for grapheme cluster based font fallback

third_party/WebKit/Source/platform/fonts/SimpleFontData.h

 /*
  * This file is part of the internal font implementation.
  *
  * Copyright (C) 2006, 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2007-2008 Torch Mobile, Inc.
  *
  * 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 164 matching lines @@
     private:
         DerivedFontData(bool custom)
             : forCustomFont(custom)
         {
         }
     };
 
     mutable OwnPtr<DerivedFontData> m_derivedFontData;
 
     RefPtr<CustomFontData> m_customFontData;
-    mutable OwnPtr<HashMap<String, bool>> m_combiningCharacterSequenceSupport;
 };
 
 ALWAYS_INLINE FloatRect SimpleFontData::boundsForGlyph(Glyph glyph) const
 {
     if (isZeroWidthSpaceGlyph(glyph))
         return FloatRect();
 
     FloatRect bounds;
     if (m_glyphToBoundsMap) {
         bounds = m_glyphToBoundsMap->metricsForGlyph(glyph);
@@ skipping 20 matching lines @@
     width = platformWidthForGlyph(glyph);
 
     m_glyphToWidthMap.setMetricsForGlyph(glyph, width);
     return width;
 }
 
 DEFINE_FONT_DATA_TYPE_CASTS(SimpleFontData, false);
 
 } // namespace blink
 #endif // SimpleFontData_h