Return width from drawText to stop re-measure in Canvas

Source/platform/fonts/mac/FontComplexTextMac.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 72 matching lines @@
 
     if (runInfo.run.rtl()) {
         initialAdvance = controller.totalWidth() - afterWidth;
         glyphBuffer.reverse();
     } else
         initialAdvance = beforeWidth;
 
     return initialAdvance;
 }
 
-void Font::drawComplexText(GraphicsContext* context, const TextRunPaintInfo& runInfo, const FloatPoint& point) const
+float Font::drawComplexText(GraphicsContext* context, const TextRunPaintInfo& runInfo, const FloatPoint& point) const
 {
     if (preferHarfBuzz(this)) {
         GlyphBuffer glyphBuffer;
         HarfBuzzShaper shaper(this, runInfo.run);
         shaper.setDrawRange(runInfo.from, runInfo.to);
         if (shaper.shape(&glyphBuffer)) {
-            drawGlyphBuffer(context, runInfo, glyphBuffer, point);
-            return;
+            return drawGlyphBuffer(context, runInfo, glyphBuffer, point);
         }
     }
     // This glyph buffer holds our glyphs + advances + font data for each glyph.
     GlyphBuffer glyphBuffer;
 
     float startX = point.x() + getGlyphsAndAdvancesForComplexText(runInfo, glyphBuffer);
 
     // We couldn't generate any glyphs for the run.  Give up.
     if (glyphBuffer.isEmpty())
-        return;
+        return 0;
 
     // Draw the glyph buffer now at the starting point returned in startX.
     FloatPoint startPoint(startX, point.y());
-    drawGlyphBuffer(context, runInfo, glyphBuffer, startPoint);
+    return drawGlyphBuffer(context, runInfo, glyphBuffer, startPoint);
 }
 
 void Font::drawEmphasisMarksForComplexText(GraphicsContext* context, const TextRunPaintInfo& runInfo, const AtomicString& mark, const FloatPoint& point) const
 {
     GlyphBuffer glyphBuffer;
     float initialAdvance = getGlyphsAndAdvancesForComplexText(runInfo, glyphBuffer, ForTextEmphasis);
 
     if (glyphBuffer.isEmpty())
         return;
 
@@ skipping 75 matching lines @@
             return simpleFontData;
     }
 
     if (!triedBaseCharacterFontData && baseCharacterGlyphData.fontData && baseCharacterGlyphData.fontData->canRenderCombiningCharacterSequence(characters, length))
         return baseCharacterGlyphData.fontData;
 
     return SimpleFontData::systemFallback();
 }
 
 } // namespace blink