Enable sync for the settings from the Extension Settings API.

chrome/common/chrome_switches.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.
 
 // Defines all the command-line switches used by Chrome.
 
 #ifndef CHROME_COMMON_CHROME_SWITCHES_H_
 #define CHROME_COMMON_CHROME_SWITCHES_H_
 #pragma once
 
@@ skipping 127 matching lines @@
 extern const char kEnableMacCookies[];
 extern const char kEnableMemoryInfo[];
 extern const char kEnableNaCl[];
 extern const char kEnableNaClDebug[];
 extern const char kEnablePanels[];
 extern const char kEnablePreconnect[];
 extern const char kEnableResourceContentSettings[];
 extern const char kEnableSearchProviderApiV2[];
 extern const char kEnableShortcutsProvider[];
 extern const char kEnableSmoothScrolling[];
+// TODO(kalman): Add to about:flags when UI for syncing extension settings has
+// been figured out.
+extern const char kEnableSyncExtensionSettings[];
 extern const char kEnableSyncOAuth[];
 extern const char kEnableSyncSearchEngines[];
 extern const char kEnableSyncTabs[];
 extern const char kEnableSyncTabsForOtherClients[];
 extern const char kEnableSyncedBookmarksFolder[];
 extern const char kEnableTabGroupsContextMenu[];
 extern const char kEnableTopSites[];
 extern const char kEnableVerticalTabs[];
 extern const char kEnableWatchdog[];
 extern const char kEnableWebSocketOverSpdy[];
@@ skipping 201 matching lines @@
 bool IsPrintPreviewEnabled();
 
 bool IsInBrowserThumbnailingEnabled();
 
 // DON'T ADD RANDOM STUFF HERE. Put it in the main section above in
 // alphabetical order, or in one of the ifdefs (also in order in each section).
 
 }  // namespace switches
 
 #endif  // CHROME_COMMON_CHROME_SWITCHES_H_