Invalidation not taking glyph bounds into account on HarfBuzz path

Source/platform/fonts/harfbuzz/FontHarfBuzz.cpp

 /*
  * Copyright (c) 2007, 2008, 2010 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 188 matching lines @@
 }
 
 float Font::getGlyphsAndAdvancesForComplexText(const TextRun& run, int from, int to, GlyphBuffer& glyphBuffer, ForTextEmphasisOrNot forTextEmphasis) const
 {
     HarfBuzzShaper shaper(this, run, HarfBuzzShaper::ForTextEmphasis);
     shaper.setDrawRange(from, to);
     shaper.shape(&glyphBuffer);
     return 0;
 }
 
-float Font::floatWidthForComplexText(const TextRun& run, HashSet<const SimpleFontData*>* /* fallbackFonts */, GlyphOverflow* /* glyphOverflow */) const
+float Font::floatWidthForComplexText(const TextRun& run, HashSet<const SimpleFontData*>* /* fallbackFonts */, GlyphOverflow* glyphOverflow) const
 {
     HarfBuzzShaper shaper(this, run);
     if (!shaper.shape())
         return 0;
+
+    if (glyphOverflow) {
+        glyphOverflow->top = std::max<int>(glyphOverflow->top, ceilf(-shaper.minGlyphBoundingBoxY()) - (glyphOverflow->computeBounds ? 0 : fontMetrics().ascent()));
+        glyphOverflow->bottom = std::max<int>(glyphOverflow->bottom, ceilf(shaper.maxGlyphBoundingBoxY()) - (glyphOverflow->computeBounds ? 0 : fontMetrics().descent()));
+        glyphOverflow->left = std::max<int>(0, ceilf(-shaper.minGlyphBoundingBoxX()));
+        glyphOverflow->right = std::max<int>(0, ceilf(shaper.maxGlyphBoundingBoxX() - shaper.totalWidth()));
+    }
     return shaper.totalWidth();
 }
 
 // Return the code point index for the given |x| offset into the text run.
 int Font::offsetForPositionForComplexText(const TextRun& run, float xFloat,
                                           bool includePartialGlyphs) const
 {
     HarfBuzzShaper shaper(this, run);
     if (!shaper.shape())
         return 0;
     return shaper.offsetForPosition(xFloat);
 }
 
 // Return the rectangle for selecting the given range of code-points in the TextRun.
 FloatRect Font::selectionRectForComplexText(const TextRun& run,
                                             const FloatPoint& point, int height,
                                             int from, int to) const
 {
     HarfBuzzShaper shaper(this, run);
     if (!shaper.shape())
         return FloatRect();
     return shaper.selectionRect(point, height, from, to);
 }
 
 } // namespace WebCore