Delete unused prefs::kHomePageChanged.

chrome/common/pref_names.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.
 
 // Constants for the names of various preferences, for easier changing.
 
 #ifndef CHROME_COMMON_PREF_NAMES_H_
 #define CHROME_COMMON_PREF_NAMES_H_
 
 #include <stddef.h>
 
 #include "build/build_config.h"
 
 #include "components/autofill/common/autofill_pref_names.h"
 
 namespace prefs {
 
 // Profile prefs. Please add Local State prefs below instead.
 extern const char kDefaultApps[];
 extern const char kDefaultAppsInstalled[];
 extern const char kDisableScreenshots[];
 extern const char kHomePageIsNewTabPage[];
 extern const char kHomePage[];
-extern const char kHomePageChanged[];
 extern const char kManagedModeLocalPassphrase[];
 extern const char kManagedModeLocalSalt[];
 extern const char kManagedModeManualHosts[];
 extern const char kManagedModeManualURLs[];
 extern const char kSessionExitedCleanly[];
 extern const char kSessionExitType[];
 extern const char kRestoreOnStartup[];
 extern const char kURLsToRestoreOnStartup[];
 extern const char kRestoreOnStartupMigrated[];
 
@@ skipping 878 matching lines @@
 extern const char kAppListLaunchCount[];
 extern const char kLastAppListAppLaunchPing[];
 extern const char kAppListAppLaunchCount[];
 
 extern const char kDRMSalt[];
 extern const char kEnableDRM[];
 
 }  // namespace prefs
 
 #endif  // CHROME_COMMON_PREF_NAMES_H_