Add a pref checkbox to enable/disable screen lock for ChromeOs.

chrome/common/pref_names.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.
 
 // Constants for the names of various preferences, for easier changing.
 
 #ifndef CHROME_COMMON_PREF_NAMES_H_
 #define CHROME_COMMON_PREF_NAMES_H_
 #pragma once
 
@@ skipping 123 matching lines @@
 extern const char kLanguageXkbRemapSearchKeyTo[];
 extern const char kLanguageXkbRemapControlKeyTo[];
 extern const char kLanguageXkbRemapAltKeyTo[];
 extern const char kLanguageXkbAutoRepeatEnabled[];
 extern const char kLanguageXkbAutoRepeatDelay[];
 extern const char kLanguageXkbAutoRepeatInterval[];
 extern const char kAccessibilityEnabled[];
 extern const char kLabsAdvancedFilesystemEnabled[];
 extern const char kLabsMediaplayerEnabled[];
 extern const char kLabsTalkEnabled[];
+extern const char kEnableScreenLock[];
 #endif
 extern const char kIpcDisabledMessages[];
 extern const char kShowHomeButton[];
 extern const char kShowPageOptionsButtons[];
 extern const char kRecentlySelectedEncoding[];
 extern const char kDeleteBrowsingHistory[];
 extern const char kDeleteDownloadHistory[];
 extern const char kDeleteCache[];
 extern const char kDeleteCookies[];
 extern const char kDeletePasswords[];
@@ skipping 226 matching lines @@
 extern const char kProxyAutoDetect[];
 extern const char kProxyServer[];
 extern const char kProxyPacUrl[];
 extern const char kProxyBypassList[];
 
 extern const char kRegisteredBackgroundContents[];
 
 }  // namespace prefs
 
 #endif  // CHROME_COMMON_PREF_NAMES_H_