Adjust visual overflow rect for rounded/shifted ascent/descent

third_party/WebKit/Source/platform/fonts/SimpleFontData.h

 /*
  * This file is part of the internal font implementation.
  *
  * Copyright (C) 2006, 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2007-2008 Torch Mobile, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 139 matching lines @@
     return m_customFontData && m_customFontData->shouldSkipDrawing();
   }
 
   const GlyphData& missingGlyphData() const { return m_missingGlyphData; }
   void setMissingGlyphData(const GlyphData& glyphData) {
     m_missingGlyphData = glyphData;
   }
 
   CustomFontData* customFontData() const { return m_customFontData.get(); }
 
+  unsigned VisualOverflowInflationForAscent() const {
+    return visual_overflow_inflation_for_ascent_;
+  }
+  unsigned VisualOverflowInflationForDescent() const {
+    return visual_overflow_inflation_for_descent_;
+  }
+
  protected:
   SimpleFontData(const FontPlatformData&,
                  PassRefPtr<CustomFontData> customData,
                  bool isTextOrientationFallback = false,
                  bool subpixelAscentDescent = false);
 
   SimpleFontData(PassRefPtr<CustomFontData> customData,
                  float fontSize,
                  bool syntheticBold,
                  bool syntheticItalic);
 
  private:
   void platformInit(bool subpixelAscentDescent);
   void platformGlyphInit();
 
   PassRefPtr<SimpleFontData> createScaledFontData(const FontDescription&,
                                                   float scaleFactor) const;
 
   FontMetrics m_fontMetrics;
   float m_maxCharWidth;
   float m_avgCharWidth;
 
   FontPlatformData m_platformData;
   SkPaint m_paint;
 
-  bool m_isTextOrientationFallback;
   RefPtr<OpenTypeVerticalData> m_verticalData;
-  bool m_hasVerticalGlyphs;
 
   Glyph m_spaceGlyph;
   float m_spaceWidth;
   Glyph m_zeroGlyph;
 
   GlyphData m_missingGlyphData;
 
   struct DerivedFontData {
     USING_FAST_MALLOC(DerivedFontData);
     WTF_MAKE_NONCOPYABLE(DerivedFontData);
 
    public:
     static std::unique_ptr<DerivedFontData> create();
 
     RefPtr<SimpleFontData> smallCaps;
     RefPtr<SimpleFontData> emphasisMark;
     RefPtr<SimpleFontData> verticalRightOrientation;
     RefPtr<SimpleFontData> uprightOrientation;
 
    private:
     DerivedFontData() {}
   };
 
   mutable std::unique_ptr<DerivedFontData> m_derivedFontData;
 
   RefPtr<CustomFontData> m_customFontData;
 
+  unsigned m_isTextOrientationFallback : 1;
+  unsigned m_hasVerticalGlyphs : 1;
+
+  // These are set to non-zero when ascent or descent is rounded or shifted
+  // to be smaller than the actual ascent or descent. When calculating visual
+  // overflows, we should add the inflations.
+  unsigned visual_overflow_inflation_for_ascent_ : 2;
+  unsigned visual_overflow_inflation_for_descent_ : 2;
+
 // See discussion on crbug.com/631032 and Skiaissue
 // https://bugs.chromium.org/p/skia/issues/detail?id=5328 :
 // On Mac we're still using path based glyph metrics, and they seem to be
 // too slow to be able to remove the caching layer we have here.
 #if OS(MACOSX)
   mutable std::unique_ptr<GlyphMetricsMap<FloatRect>> m_glyphToBoundsMap;
   mutable GlyphMetricsMap<float> m_glyphToWidthMap;
 #endif
 };
 
@@ skipping 29 matching lines @@
 
   m_glyphToWidthMap.setMetricsForGlyph(glyph, width);
   return width;
 #endif
 }
 
 DEFINE_FONT_DATA_TYPE_CASTS(SimpleFontData, false);
 
 }  // namespace blink
 #endif  // SimpleFontData_h