Introduce DEFINE_CUSTOM_FONT_DATA_TYPE_CASTS, and use it

Source/platform/fonts/CustomFontData.h

 /*
  * Copyright (C) 2013 Google, 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 38 matching lines @@
     virtual bool isSVGFont() const { return false; }
     virtual void initializeFontData(SimpleFontData*, float) { }
     virtual float widthForSVGGlyph(Glyph, float) const { return 0.0f; }
     virtual bool fillSVGGlyphPage(GlyphPage*, unsigned, unsigned, UChar*, unsigned, const SimpleFontData*) const { return false; }
     virtual bool applySVGGlyphSelection(WidthIterator&, GlyphData&, bool, int, unsigned&) const { return false; }
 
 protected:
     CustomFontData() { }
 };
 
+#define DEFINE_CUSTOM_FONT_DATA_TYPE_CASTS(thisType, predicate) \

[tkent, 2014/08/11 01:04:56]

I feel introducing new macro only for SVGFontData is overkill.  But it's ok.

[gyuyoung-inactive, 2014/08/11 04:50:55]

If there is only SVGFontData as child class of CustomFontData class, I didn't
use this. But, there are two more child classes(CSSCustomFontData and
TestCustomFontData) though they don't use type casting yet. So, I add new macro
so that those classes also will use this macro in future.

+    template<typename T> inline thisType* to##thisType(const RefPtr<T>& customFontData) { return to##thisType(customFontData.get()); } \
+    DEFINE_TYPE_CASTS(thisType, CustomFontData, customFontData, customFontData->predicate, customFontData.predicate)
+
 }
 
 #endif // CustomFontData_h