Add onChanged events to the extension settings API, both from sync and between

chrome/browser/extensions/extension_service.cc

 // 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.
 
 #include "chrome/browser/extensions/extension_service.h"
 
 #include <algorithm>
 #include <set>
 
 #include "base/bind.h"
@@ skipping 573 matching lines @@
 
 ExtensionService::ExtensionService(Profile* profile,
                                    const CommandLine* command_line,
                                    const FilePath& install_directory,
                                    ExtensionPrefs* extension_prefs,
                                    bool autoupdate_enabled,
                                    bool extensions_enabled)
     : weak_ptr_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)),
       profile_(profile),
       extension_prefs_(extension_prefs),
-      extension_settings_frontend_(
-          profile->GetPath().AppendASCII(kSettingsDirectoryName)),
+      extension_settings_frontend_(profile),
       pending_extension_manager_(*ALLOW_THIS_IN_INITIALIZER_LIST(this)),
       install_directory_(install_directory),
       extensions_enabled_(extensions_enabled),
       show_extensions_prompts_(true),
       ready_(false),
       toolbar_model_(ALLOW_THIS_IN_INITIALIZER_LIST(this)),
       menu_manager_(profile),
       app_notification_manager_(new AppNotificationManager(profile)),
       permissions_manager_(ALLOW_THIS_IN_INITIALIZER_LIST(this)),
       apps_promo_(profile->GetPrefs()),
@@ skipping 2410 matching lines @@
 
 ExtensionService::NaClModuleInfoList::iterator
     ExtensionService::FindNaClModule(const GURL& url) {
   for (NaClModuleInfoList::iterator iter = nacl_module_list_.begin();
        iter != nacl_module_list_.end(); ++iter) {
     if (iter->url == url)
       return iter;
   }
   return nacl_module_list_.end();
 }