clang/win: Attempt to fix component build after r194273.

Source/platform/fonts/shaping/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 61 matching lines @@
         if (runIndex < m_harfBuzzRuns.size()) {
             startIndex = m_harfBuzzRuns[runIndex]->startIndex();
             numGlyphs = m_harfBuzzRuns[runIndex]->numGlyphs();
             script = m_harfBuzzRuns[runIndex]->script();
             return true;
         }
         return false;
     }
 
 private:
-    class HarfBuzzRun {
+    class PLATFORM_EXPORT HarfBuzzRun {
     public:
         HarfBuzzRun(const HarfBuzzRun&);
         ~HarfBuzzRun();
 
         static PassOwnPtr<HarfBuzzRun> create(const SimpleFontData* fontData, unsigned startIndex, unsigned numCharacters, hb_direction_t direction, hb_script_t script)
         {
             return adoptPtr(new HarfBuzzRun(fontData, startIndex, numCharacters, direction, script));
         }
 
         void applyShapeResult(hb_buffer_t*);
@@ skipping 68 matching lines @@
     int m_toIndex;
 
     float m_totalWidth;
 
     friend struct CachedShapingResults;
 };
 
 } // namespace blink
 
 #endif // HarfBuzzShaper_h