Reland "Change fallback font collection in HarfBuzzShaper"

Source/platform/fonts/shaping/CachingWordShaper.cpp

 /*
  * Copyright (C) 2015 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 38 matching lines @@
     if (m_shapeCache)
         m_shapeCache->clear();
 }
 
 float CachingWordShaper::width(const Font* font, const TextRun& run,
     HashSet<const SimpleFontData*>* fallbackFonts,
     FloatRect* glyphBounds)
 {
     float width = 0;
     RefPtr<ShapeResult> wordResult;
-    CachingWordShapeIterator iterator(m_shapeCache, run, font, fallbackFonts);
+    CachingWordShapeIterator iterator(m_shapeCache, run, font);
     while (iterator.next(&wordResult)) {
         if (wordResult) {
             width += wordResult->width();
             if (glyphBounds)
                 glyphBounds->unite(wordResult->bounds());
+            if (fallbackFonts)
+                wordResult->fallbackFonts(fallbackFonts);
         }
     }
 
     return width;
 }
 
 static inline float shapeResultsForRun(ShapeCache* shapeCache, const Font* font,
     const TextRun& run, HashSet<const SimpleFontData*>* fallbackFonts,
     Vector<RefPtr<ShapeResult>>* results)
 {
-    CachingWordShapeIterator iterator(shapeCache, run, font, fallbackFonts);
+    CachingWordShapeIterator iterator(shapeCache, run, font);
     RefPtr<ShapeResult> wordResult;
     float totalWidth = 0;
     while (iterator.next(&wordResult)) {
         if (wordResult) {
             results->append(wordResult);
             totalWidth += wordResult->width();
+            if (fallbackFonts)
+                wordResult->fallbackFonts(fallbackFonts);
         }
     }
     return totalWidth;
 }
 
 float CachingWordShaper::fillGlyphBuffer(const Font* font, const TextRun& run,
     HashSet<const SimpleFontData*>* fallbackFonts,
     GlyphBuffer* glyphBuffer, unsigned from, unsigned to)
 {
     Vector<RefPtr<ShapeResult>> results;
@@ skipping 18 matching lines @@
 {
     Vector<RefPtr<ShapeResult>> results;
     float totalWidth = shapeResultsForRun(m_shapeCache, font, run, nullptr,
         &results);
 
     return ShapeResult::selectionRect(results, run.direction(), totalWidth,
         point, height, from, to);
 }
 
 }; // namespace blink