Revert of Remove unused FontPlatformDataHarfBuzz::emSizeInFontUnits

Source/platform/fonts/harfbuzz/FontPlatformDataHarfBuzz.h

 /*
  * Copyright (c) 2006, 2007, 2008, 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 75 matching lines @@
 
     // -------------------------------------------------------------------------
     // Return Skia's unique id for this font. This encodes both the style and
     // the font's file name so refers to a single face.
     // -------------------------------------------------------------------------
     SkFontID uniqueID() const;
     SkTypeface* typeface() const { return m_typeface.get(); }
 
     unsigned hash() const;
     float size() const { return m_textSize; }
+    int emSizeInFontUnits() const;
 
     FontOrientation orientation() const { return m_orientation; }
     void setOrientation(FontOrientation orientation) { m_orientation = orientation; }
     void setSyntheticBold(bool syntheticBold) { m_syntheticBold = syntheticBold; }
     void setSyntheticItalic(bool syntheticItalic) { m_syntheticItalic = syntheticItalic; }
     bool operator==(const FontPlatformData&) const;
     FontPlatformData& operator=(const FontPlatformData&);
     bool isHashTableDeletedValue() const { return m_isHashTableDeletedValue; }
 
 #if ENABLE(OPENTYPE_VERTICAL)
@@ skipping 19 matching lines @@
     static void setAntiAlias(bool);
     static void setSubpixelRendering(bool);
 
 private:
     void getRenderStyleForStrike(const char*, int);
     void querySystemForRenderStyle(bool useSkiaSubpixelPositioning);
 
     RefPtr<SkTypeface> m_typeface;
     CString m_family;
     float m_textSize;
+    mutable int m_emSizeInFontUnits;
     bool m_syntheticBold;
     bool m_syntheticItalic;
     FontOrientation m_orientation;
     FontRenderStyle m_style;
     mutable RefPtr<HarfBuzzFace> m_harfBuzzFace;
     bool m_isHashTableDeletedValue;
 };
 
 } // namespace WebCore
 
 #endif // ifdef FontPlatformDataHarfBuzz_h