Adds a gfx_export.h to ui/gfx and converts all code in ui/gfx to

ui/gfx/platform_font_win.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_GFX_PLATFORM_FONT_WIN_H_
 #define UI_GFX_PLATFORM_FONT_WIN_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
-#include "ui/base/ui_export.h"
+#include "ui/gfx/gfx_export.h"
 #include "ui/gfx/platform_font.h"
 
 namespace gfx {
 
 class UI_EXPORT PlatformFontWin : public PlatformFont {
  public:
   PlatformFontWin();
   explicit PlatformFontWin(NativeFont native_font);
   PlatformFontWin(const std::string& font_name, int font_size);
 
@@ skipping 126 matching lines @@
   // Indirect reference to the HFontRef, which references the underlying HFONT.
   scoped_refptr<HFontRef> font_ref_;
 
   DISALLOW_COPY_AND_ASSIGN(PlatformFontWin);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_PLATFORM_FONT_WIN_H_