When the user navigates to the home page, make sure to set the RLZ string

chrome/common/pref_names.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.
 
 // Constants for the names of various preferences, for easier changing.
 
 #ifndef CHROME_COMMON_PREF_NAMES_H_
 #define CHROME_COMMON_PREF_NAMES_H_
 #pragma once
 
 #include <stddef.h>
 
 #include "build/build_config.h"
 
 namespace prefs {
 
 // Profile prefs. Please add Local State prefs below instead.
 extern const char kAppsPromoCounter[];
 extern const char kDefaultAppsInstalled[];
 extern const char kHomePageIsNewTabPage[];
 extern const char kHomePage[];
+extern const char kHomePageChanged[];
 extern const char kSessionExitedCleanly[];
 extern const char kRestoreOnStartup[];
 extern const char kURLsToRestoreOnStartup[];
 extern const char kSyncPromoExpanded[];
 
 // For OS_CHROMEOS we maintain kApplicationLocale property in both local state
 // and user's profile.  Global property determines locale of login screen,
 // while user's profile determines his personal locale preference.
 extern const char kApplicationLocale[];
 #if defined(OS_CHROMEOS)
@@ skipping 552 matching lines @@
 
 extern const char kUserCreatedLoginItem[];
 extern const char kBackgroundModeEnabled[];
 
 extern const char kDevicePolicyRefreshRate[];
 extern const char kUserPolicyRefreshRate[];
 
 }  // namespace prefs
 
 #endif  // CHROME_COMMON_PREF_NAMES_H_