Fix syncing of system theme on Linux

chrome/browser/themes/theme_service.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 CHROME_BROWSER_THEMES_THEME_SERVICE_H_
 #define CHROME_BROWSER_THEMES_THEME_SERVICE_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 92 matching lines @@
   // ExtensionService.
   virtual void SetTheme(const extensions::Extension* extension);
 
   // Reset the theme to default.
   virtual void UseDefaultTheme();
 
   // Set the current theme to the system theme. On some platforms, the system
   // theme is the default theme.
   virtual void UseSystemTheme();
 
+  // Returns true if the default theme and system theme are not the same on
+  // this platform.
+  virtual bool IsSystemThemeDistinctFromDefaultTheme() const;
+
   // Whether we're using the chrome default theme. Virtual so linux can check
   // if we're using the GTK theme.
   virtual bool UsingDefaultTheme() const;
 
   // Gets the id of the last installed theme. (The theme may have been further
   // locally customized.)
   virtual std::string GetThemeID() const;
 
   // This class needs to keep track of the number of theme infobars so that we
   // clean up unused themes.
@@ skipping 119 matching lines @@
   content::NotificationRegistrar registrar_;
 
   scoped_ptr<ThemeSyncableService> theme_syncable_service_;
 
   base::WeakPtrFactory<ThemeService> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ThemeService);
 };
 
 #endif  // CHROME_BROWSER_THEMES_THEME_SERVICE_H_