chrome: Cleanup class/struct forward declarations

chrome/browser/extensions/theme_installed_infobar_delegate.h

 // Copyright (c) 2011 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_EXTENSIONS_THEME_INSTALLED_INFOBAR_DELEGATE_H_
 #define CHROME_BROWSER_EXTENSIONS_THEME_INSTALLED_INFOBAR_DELEGATE_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "components/infobars/core/confirm_infobar_delegate.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
 class ExtensionService;
-class InfoBarService;
 class Profile;
 class ThemeService;
 
 namespace extensions {
 class Extension;
 }
 
 // When a user installs a theme, we display it immediately, but provide an
 // infobar allowing them to cancel.
 class ThemeInstalledInfoBarDelegate : public ConfirmInfoBarDelegate,
@@ skipping 40 matching lines @@
 
   // Used to undo theme install.
   std::string previous_theme_id_;
   bool previous_using_system_theme_;
 
   // Registers and unregisters us for notifications.
   content::NotificationRegistrar registrar_;
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_THEME_INSTALLED_INFOBAR_DELEGATE_H_