Added user settings to chrome://supervised-user-internals.

chrome/browser/supervised_user/supervised_user_settings_service.cc

 // Copyright 2014 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/supervised_user/supervised_user_settings_service.h"
 
 #include "base/callback.h"
 #include "base/json/json_reader.h"
 #include "base/json/json_writer.h"
 #include "base/prefs/json_pref_store.h"
@@ skipping 67 matching lines @@
   }
 }
 
 void SupervisedUserSettingsService::Init(
     scoped_refptr<PersistentPrefStore> store) {
   DCHECK(!store_.get());
   store_ = store;
   store_->AddObserver(this);
 }
 
-void SupervisedUserSettingsService::Subscribe(
+scoped_ptr<SupervisedUserSettingsService::SettingsCallbackList::Subscription>
+    SupervisedUserSettingsService::Subscribe(
     const SettingsCallback& callback) {
   if (IsReady()) {
     scoped_ptr<base::DictionaryValue> settings = GetSettings();
     callback.Run(settings.get());
   }
 
-  subscribers_.push_back(callback);
+  return callback_list_.Add(callback);
 }
 
 void SupervisedUserSettingsService::SetActive(bool active) {
   active_ = active;
   InformSubscribers();
 }
 
 bool SupervisedUserSettingsService::IsReady() {
   // Initialization cannot be complete but have failed at the same time.
   DCHECK(!(store_->IsInitializationComplete() && initialization_failed_));
@@ skipping 293 matching lines @@
   }
 
   return settings.Pass();
 }
 
 void SupervisedUserSettingsService::InformSubscribers() {
   if (!IsReady())
     return;
 
   scoped_ptr<base::DictionaryValue> settings = GetSettings();
-  for (const auto& callback : subscribers_)
-    callback.Run(settings.get());
+  callback_list_.Notify(settings.get());
 }