Change Font::offsetForPositionForComplexText to use CachingWordShapeIterator

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 50 matching lines @@
         if (wordResult) {
             width += wordResult->width();
             if (glyphBounds)
                 glyphBounds->unite(wordResult->bounds());
         }
     }
 
     return width;
 }
 
+int CachingWordShaper::offsetForPosition(const Font* font, const TextRun& run, float targetX)
+{
+    HashSet<const SimpleFontData*> fallbackFonts;
+    CachingWordShapeIterator iterator(m_shapeCache, run, font, &fallbackFonts);
+    return ShapeResult::offsetForPosition(iterator, run, targetX);
+}
+
 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);
     RefPtr<ShapeResult> wordResult;
     float totalWidth = 0;
     while (iterator.next(&wordResult)) {
         if (wordResult) {
             results->append(wordResult);
@@ skipping 29 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