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 146 matching lines @@
     return custom_font_data_ && custom_font_data_->ShouldSkipDrawing();
   }
 
   const GlyphData& MissingGlyphData() const { return missing_glyph_data_; }
   void SetMissingGlyphData(const GlyphData& glyph_data) {
     missing_glyph_data_ = glyph_data;
   }
 
   CustomFontData* GetCustomFontData() const { return custom_font_data_.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> custom_data,
                  bool is_text_orientation_fallback = false,
                  bool subpixel_ascent_descent = false);
 
   // Only used for testing.
   SimpleFontData(const FontPlatformData&, PassRefPtr<OpenTypeVerticalData>);
 
  private:
   void PlatformInit(bool subpixel_ascent_descent);
   void PlatformGlyphInit();
 
   PassRefPtr<SimpleFontData> CreateScaledFontData(const FontDescription&,
                                                   float scale_factor) const;
 
   FontMetrics font_metrics_;
   float max_char_width_;
   float avg_char_width_;
 
   FontPlatformData platform_data_;
   SkPaint paint_;
 
-  bool is_text_orientation_fallback_;
   RefPtr<OpenTypeVerticalData> vertical_data_;
-  bool has_vertical_glyphs_;
 
   Glyph space_glyph_;
   float space_width_;
   Glyph zero_glyph_;
 
   GlyphData missing_glyph_data_;
 
   struct DerivedFontData {
     USING_FAST_MALLOC(DerivedFontData);
     WTF_MAKE_NONCOPYABLE(DerivedFontData);
 
    public:
     static std::unique_ptr<DerivedFontData> Create();
 
     RefPtr<SimpleFontData> small_caps;
     RefPtr<SimpleFontData> emphasis_mark;
     RefPtr<SimpleFontData> vertical_right_orientation;
     RefPtr<SimpleFontData> upright_orientation;
 
    private:
     DerivedFontData() {}
   };
 
   mutable std::unique_ptr<DerivedFontData> derived_font_data_;
 
   RefPtr<CustomFontData> custom_font_data_;
 
+  unsigned is_text_orientation_fallback_ : 1;
+  unsigned has_vertical_glyphs_ : 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>> glyph_to_bounds_map_;
   mutable GlyphMetricsMap<float> glyph_to_width_map_;
 #endif
 };
 
@@ skipping 29 matching lines @@
 
   glyph_to_width_map_.SetMetricsForGlyph(glyph, width);
   return width;
 #endif
 }
 
 DEFINE_FONT_DATA_TYPE_CASTS(SimpleFontData, false);
 
 }  // namespace blink
 #endif  // SimpleFontData_h