Clean up forward declarations in Source/platform

Source/platform/fonts/Font.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2006, 2007, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Holger Hans Peter Freyther
  *
  * 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
@@ skipping 34 matching lines @@
 
 class SkTextBlob;
 struct SkPoint;
 
 namespace blink {
 
 class FloatPoint;
 class FloatRect;
 class FontData;
 class FontMetrics;
-class FontPlatformData;
 class FontSelector;
 class GlyphBuffer;
 class GraphicsContext;
 class TextRun;
 struct TextRunPaintInfo;
 
 struct GlyphData;
 
 struct GlyphOverflow {
     GlyphOverflow()
@@ skipping 159 matching lines @@
 {
     if (!tabSize)
         return fontDescription().letterSpacing();
     float tabWidth = tabSize * fontData.spaceWidth() + fontDescription().letterSpacing();
     return tabWidth - fmodf(position, tabWidth);
 }
 
 } // namespace blink
 
 #endif