Implement pref policy for disabling incognito mode.

chrome/browser/ui/browser.h

-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// 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_UI_BROWSER_H_
 #define CHROME_BROWSER_UI_BROWSER_H_
 #pragma once
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 1091 matching lines @@
 
   // Keep track of the printing enabled pref.
   BooleanPrefMember printing_enabled_;
 
   // Keep track of the development tools disabled pref.
   BooleanPrefMember dev_tools_disabled_;
 
   // Keep track of when instant enabled changes.
   BooleanPrefMember instant_enabled_;
 
+  // Tracks the preference that controls whether incognito mode is allowed.
+  BooleanPrefMember incognito_mode_allowed_;
+
   // Indicates if command execution is blocked.
   bool block_command_execution_;
 
   // Stores the last blocked command id when |block_command_execution_| is true.
   int last_blocked_command_id_;
 
   // Stores the disposition type of the last blocked command.
   WindowOpenDisposition last_blocked_command_disposition_;
 
   // Different types of action when web app info is available.
@@ skipping 15 matching lines @@
   // and we install ourselves as an observer.
   TabRestoreService* tab_restore_service_;
 
   scoped_ptr<InstantController> instant_;
   scoped_ptr<InstantUnloadHandler> instant_unload_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(Browser);
 };
 
 #endif  // CHROME_BROWSER_UI_BROWSER_H_