Reland "Change fallback font collection in HarfBuzzShaper"

Source/platform/fonts/Font.cpp

Index: Source/platform/fonts/Font.cpp
diff --git a/Source/platform/fonts/Font.cpp b/Source/platform/fonts/Font.cpp
index ef71b8fe2dcbe79e8b3884336d256b0f6b7685f2..36aaf674fa30c829a3ad41331af011c974918839 100644
--- a/Source/platform/fonts/Font.cpp
+++ b/Source/platform/fonts/Font.cpp
@@ -704,8 +704,7 @@ float Font::floatWidthForComplexText(const TextRun& run, HashSet<const SimpleFon
 int Font::offsetForPositionForComplexText(const TextRun& run, float xFloat,
     bool includePartialGlyphs) const
 {
-    HashSet<const SimpleFontData*> fallbackFonts;
-    HarfBuzzShaper shaper(this, run, &fallbackFonts);
+    HarfBuzzShaper shaper(this, run);
     RefPtr<ShapeResult> shapeResult = shaper.shapeResult();
     if (!shapeResult)
         return 0;