Use the correct font metrics in base PlatformFontWin if DirectWrite is used in the browser for font…

ui/gfx/platform_font_win.h

Index: ui/gfx/platform_font_win.h
diff --git a/ui/gfx/platform_font_win.h b/ui/gfx/platform_font_win.h
index 90160aa6049ccc3ad8afc7bc046b2c3ca66ef618..27bad4d0b4719b448f904631c7766a1d3f0fc830 100644
--- a/ui/gfx/platform_font_win.h
+++ b/ui/gfx/platform_font_win.h
@@ -5,6 +5,7 @@
 #ifndef UI_GFX_PLATFORM_FONT_WIN_H_
 #define UI_GFX_PLATFORM_FONT_WIN_H_
 
+#include <dwrite.h>
 #include <string>
 
 #include "base/compiler_specific.h"
@@ -66,6 +67,11 @@ class GFX_EXPORT PlatformFontWin : public PlatformFont {
   virtual const FontRenderParams& GetFontRenderParams() const override;
   virtual NativeFont GetNativeFont() const override;
 
+  // Called once during initialization if we are using DirectWrite for fonts.
+  static void set_direct_write_factory(IDWriteFactory* factory) {
+    direct_write_factory_ = factory;
+  }
+
  private:
   virtual ~PlatformFontWin() {}
 
@@ -151,6 +157,13 @@ class GFX_EXPORT PlatformFontWin : public PlatformFont {
   // |base_font|.
   static Font DeriveWithCorrectedSize(HFONT base_font);
 
+  // Converts the GDI font identified by the |gdi_font| parameter to a
+  // DirectWrite compatible HFONT, i.e with metrics compatible with
+  // DirectWrite.
+  // Returns the HFONT which is created from DirectWrite compatible font
+  // metrics.
+  static HFONT ConvertGDIFontToDirectWriteFont(HFONT gdi_font);
+
   // Creates a new PlatformFontWin with the specified HFontRef. Used when
   // constructing a Font from a HFONT we don't want to copy.
   explicit PlatformFontWin(HFontRef* hfont_ref);
@@ -161,6 +174,10 @@ class GFX_EXPORT PlatformFontWin : public PlatformFont {
   // Indirect reference to the HFontRef, which references the underlying HFONT.
   scoped_refptr<HFontRef> font_ref_;
 
+  // Pointer to the global IDWriteFactory interface. This is only set if we are
+  // using DirectWrite for fonts. Defaults to NULL.
+  static IDWriteFactory* direct_write_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(PlatformFontWin);
 };