Revert 71167 - Remove wstring from gfx....

gfx/platform_font_mac.h

 // Copyright (c) 2010 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 GFX_PLATFORM_FONT_MAC_
 #define GFX_PLATFORM_FONT_MAC_
 #pragma once
 
 #include "gfx/platform_font.h"
 
 namespace gfx {
 
 class PlatformFontMac : public PlatformFont {
  public:
   PlatformFontMac();
   explicit PlatformFontMac(const Font& other);
   explicit PlatformFontMac(NativeFont native_font);
-  PlatformFontMac(const string16& font_name,
+  PlatformFontMac(const std::wstring& font_name,
                   int font_size);
 
   // Overridden from PlatformFont:
   virtual Font DeriveFont(int size_delta, int style) const;
   virtual int GetHeight() const;
   virtual int GetBaseline() const;
   virtual int GetAverageCharacterWidth() const;
   virtual int GetStringWidth(const string16& text) const;
   virtual int GetExpectedTextWidth(int length) const;
   virtual int GetStyle() const;
-  virtual string16 GetFontName() const;
+  virtual const std::wstring& GetFontName() const;
   virtual int GetFontSize() const;
   virtual NativeFont GetNativeFont() const;
 
  private:
-  PlatformFontMac(const string16& font_name, int font_size, int style);
+  PlatformFontMac(const std::wstring& font_name, int font_size, int style);
   virtual ~PlatformFontMac() {}
 
   // Initialize the object with the specified parameters.
-  void InitWithNameSizeAndStyle(const string16& font_name,
+  void InitWithNameSizeAndStyle(const std::wstring& font_name,
                                 int font_size,
                                 int style);
 
   // Calculate and cache the font metrics.
   void CalculateMetrics();
 
-  string16 font_name_;
+  std::wstring font_name_;
   int font_size_;
   int style_;
 
   // Cached metrics, generated at construction
   int height_;
   int ascent_;
   int average_width_;
 };
 
 }  // namespace gfx
 
 #endif  // GFX_PLATFORM_FONT_MAC_