Remove glyph metrics caching on non-Mac platforms

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 12 matching lines @@
 
 #ifndef SimpleFontData_h
 #define SimpleFontData_h
 
 #include "platform/PlatformExport.h"
 #include "platform/fonts/CustomFontData.h"
 #include "platform/fonts/FontBaseline.h"
 #include "platform/fonts/FontData.h"
 #include "platform/fonts/FontMetrics.h"
 #include "platform/fonts/FontPlatformData.h"
-#include "platform/fonts/GlyphMetricsMap.h"
 #include "platform/fonts/GlyphPageTreeNode.h"
 #include "platform/fonts/TypesettingFeatures.h"
 #include "platform/fonts/opentype/OpenTypeVerticalData.h"
 #include "platform/geometry/FloatRect.h"
 #include "wtf/PtrUtil.h"
 #include "wtf/text/StringHash.h"
 #include <SkPaint.h>
 #include <memory>
 
+#if OS(MACOSX)
+#include "platform/fonts/GlyphMetricsMap.h"
+#endif
+
 namespace blink {
 
 class FontDescription;
 
 enum FontDataVariant { AutoVariant, NormalVariant, SmallCapsVariant, EmphasisMarkVariant };
 
 class PLATFORM_EXPORT SimpleFontData : public FontData {
 public:
     // Used to create platform fonts.
     static PassRefPtr<SimpleFontData> create(const FontPlatformData& platformData, PassRefPtr<CustomFontData> customData = nullptr, bool isTextOrientationFallback = false)
@@ skipping 84 matching lines @@
     void platformInit();
     void platformGlyphInit();
 
     PassRefPtr<SimpleFontData> createScaledFontData(const FontDescription&, float scaleFactor) const;
 
     FontMetrics m_fontMetrics;
     float m_maxCharWidth;
     float m_avgCharWidth;
 
     FontPlatformData m_platformData;
-    mutable std::unique_ptr<GlyphMetricsMap<FloatRect>> m_glyphToBoundsMap;
-    mutable GlyphMetricsMap<float> m_glyphToWidthMap;
     SkPaint m_paint;
 
     bool m_isTextOrientationFallback;
     RefPtr<OpenTypeVerticalData> m_verticalData;
     bool m_hasVerticalGlyphs;
 
     Glyph m_spaceGlyph;
     float m_spaceWidth;
     Glyph m_zeroGlyph;
 
@@ skipping 15 matching lines @@
     private:
         DerivedFontData(bool custom)
             : forCustomFont(custom)
         {
         }
     };
 
     mutable std::unique_ptr<DerivedFontData> m_derivedFontData;
 
     RefPtr<CustomFontData> m_customFontData;
+
+    // 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
 };
 
 
 ALWAYS_INLINE FloatRect SimpleFontData::boundsForGlyph(Glyph glyph) const
 {
+#if !OS(MACOSX)
+    return platformBoundsForGlyph(glyph);
+#else
     FloatRect boundsResult;
     if (m_glyphToBoundsMap) {
         boundsResult = m_glyphToBoundsMap->metricsForGlyph(glyph);
         if (boundsResult.width() != cGlyphSizeUnknown)
             return boundsResult;
     }
 
     boundsResult = platformBoundsForGlyph(glyph);
     if (!m_glyphToBoundsMap)
         m_glyphToBoundsMap = wrapUnique(new GlyphMetricsMap<FloatRect>);
     m_glyphToBoundsMap->setMetricsForGlyph(glyph, boundsResult);
 
     return boundsResult;
+#endif
 }
 
 ALWAYS_INLINE float SimpleFontData::widthForGlyph(Glyph glyph) const
 {
+#if !OS(MACOSX)
+    return platformWidthForGlyph(glyph);
+#else
     float width = m_glyphToWidthMap.metricsForGlyph(glyph);
     if (width != cGlyphSizeUnknown)
         return width;
 
     width = platformWidthForGlyph(glyph);
 
     m_glyphToWidthMap.setMetricsForGlyph(glyph, width);
     return width;
+#endif
 }
 
 DEFINE_FONT_DATA_TYPE_CASTS(SimpleFontData, false);
 
 } // namespace blink
 #endif // SimpleFontData_h