Optimize Complex Text Shaping and Caching

Source/platform/fonts/shaping/HarfBuzzFace.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 @@
 public:
     static const hb_tag_t vertTag;
     static const hb_tag_t vrt2Tag;
 
     static PassRefPtr<HarfBuzzFace> create(FontPlatformData* platformData, uint64_t uniqueID)
     {
         return adoptRef(new HarfBuzzFace(platformData, uniqueID));
     }
     ~HarfBuzzFace();
 
-    hb_font_t* createFont();
+    hb_font_t* createFont() const;
+    hb_face_t* face() const { return m_face; }
 
     void setScriptForVerticalGlyphSubstitution(hb_buffer_t*);
 
 private:
     HarfBuzzFace(FontPlatformData*, uint64_t);
 
     hb_face_t* createFace();
 
     FontPlatformData* m_platformData;
     uint64_t m_uniqueID;
     hb_face_t* m_face;
     WTF::HashMap<uint32_t, uint16_t>* m_glyphCacheForFaceCacheEntry;
 
     hb_script_t m_scriptForVerticalText;
 };
 
 } // namespace blink
 
 #endif // HarfBuzzFace_h