Create an antialiased virtual layout test group for font testing on Mac

Source/platform/fonts/mac/FontMac.cpp

 /*
  * Copyright (c) 2011 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 87 matching lines @@
         shouldAntialias = false;
         shouldSmoothFonts = false;
         break;
     case AutoSmoothing:
         // For the AutoSmooth case, don't do anything! Keep the default settings.
         break;
     }
 
     if (isRunningLayoutTest()) {
         shouldSmoothFonts = false;
-        shouldAntialias = false;
+        shouldAntialias = shouldAntialias && isFontAntialiasingEnabledForTest();
     }
 
     const GlyphBufferGlyph* glyphs = glyphBuffer.glyphs(from);
     SkScalar x = SkFloatToScalar(point.x());
     SkScalar y = SkFloatToScalar(point.y());
 
     if (font->platformData().orientation() == Vertical)
         y += SkFloatToScalar(font->fontMetrics().floatAscent(IdeographicBaseline) - font->fontMetrics().floatAscent());
     // FIXME: text rendering speed:
     // Android has code in their WebCore fork to special case when the
@@ skipping 48 matching lines @@
             paint.setLooper(0);
         }
 
         gc->drawPosText(glyphs, numGlyphs * sizeof(uint16_t), pos, textRect, paint);
     }
     if (font->platformData().orientation() == Vertical)
         gc->restore();
 }
 
 } // namespace WebCore