Implement CSS Emphasis Marks for complex text

Source/platform/fonts/harfbuzz/HarfBuzzShaper.h

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 35 matching lines @@
 class Font;
 class SimpleFontData;
 
 class HarfBuzzShaper FINAL {
 public:
     enum NormalizeMode {
         DoNotNormalizeMirrorChars,
         NormalizeMirrorChars
     };
 
-    HarfBuzzShaper(const Font*, const TextRun&);
+    enum ForTextEmphasisOrNot {
+        NotForTextEmphasis,
+        ForTextEmphasis
+    };
+
+    HarfBuzzShaper(const Font*, const TextRun&, bool forTextEmphasis = false);
 
     void setDrawRange(int from, int to);
     bool shape(GlyphBuffer* = 0);
     FloatPoint adjustStartPoint(const FloatPoint&);
     float totalWidth() { return m_totalWidth; }
     int offsetForPosition(float targetX);
     FloatRect selectionRect(const FloatPoint&, int height, int from, int to);
 
 private:
     class HarfBuzzRun {
@@ skipping 83 matching lines @@
     float m_letterSpacing; // Pixels to be added after each glyph.
 
     Vector<hb_feature_t, 4> m_features;
     Vector<OwnPtr<HarfBuzzRun>, 16> m_harfBuzzRuns;
 
     FloatPoint m_startOffset;
 
     int m_fromIndex;
     int m_toIndex;
 
+    bool m_forTextEmphasis;
+
     float m_totalWidth;
 
     friend struct CachedShapingResults;
 };
 
 } // namespace WebCore
 
 #endif // HarfBuzzShaper_h