Remove NOTIFICATION_SYSTEM_SETTING_CHANGED, switch CrosSettings to base::CallbackRegistry.

chrome/browser/chromeos/policy/app_pack_updater.cc

 // 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.
 
 #include "chrome/browser/chromeos/policy/app_pack_updater.h"
 
 #include "base/bind.h"
 #include "base/values.h"
-#include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/policy/enterprise_install_attributes.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/cros_settings_names.h"
 #include "chrome/browser/extensions/external_loader.h"
 #include "chrome/browser/extensions/external_provider_impl.h"
 #include "content/public/browser/browser_thread.h"
-#include "content/public/browser/notification_details.h"
-#include "content/public/browser/notification_service.h"
-#include "content/public/browser/notification_source.h"
 
 using content::BrowserThread;
 
 namespace policy {
 
 namespace {
 
 // Directory where the AppPack extensions are cached.
 const char kAppPackCacheDir[] = "/var/cache/app_pack";
 
@@ skipping 31 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(AppPackExternalLoader);
 };
 
 AppPackUpdater::AppPackUpdater(net::URLRequestContextGetter* request_context,
                                EnterpriseInstallAttributes* install_attributes)
     : weak_ptr_factory_(this),
       created_extension_loader_(false),
       install_attributes_(install_attributes),
       external_cache_(kAppPackCacheDir, request_context, this, false) {
-  chromeos::CrosSettings::Get()->AddSettingsObserver(chromeos::kAppPack, this);
+  app_pack_subscription_ = chromeos::CrosSettings::Get()->AddSettingsObserver(
+      chromeos::kAppPack,
+      base::Bind(&AppPackUpdater::AppPackChanged, base::Unretained(this)));
 
   if (install_attributes_->GetMode() == DEVICE_MODE_RETAIL_KIOSK) {
     // Already in Kiosk mode, start loading.
     BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                             base::Bind(&AppPackUpdater::LoadPolicy,
                                        weak_ptr_factory_.GetWeakPtr()));
   } else {
     // Linger until the device switches to DEVICE_MODE_RETAIL_KIOSK and the
     // app pack device setting appears.
   }
 }
 
 AppPackUpdater::~AppPackUpdater() {
-  chromeos::CrosSettings::Get()->RemoveSettingsObserver(
-      chromeos::kAppPack, this);
 }
 
 extensions::ExternalLoader* AppPackUpdater::CreateExternalLoader() {
   if (created_extension_loader_) {
     NOTREACHED();
     return NULL;
   }
   created_extension_loader_ = true;
   AppPackExternalLoader* loader = new AppPackExternalLoader();
   extension_loader_ = loader->AsWeakPtr();
 
   // The cache may have been already checked. In that case, load the current
   // extensions into the loader immediately.
   UpdateExtensionLoader();
 
   return loader;
 }
 
 void AppPackUpdater::SetScreenSaverUpdateCallback(
     const AppPackUpdater::ScreenSaverUpdateCallback& callback) {
   screen_saver_update_callback_ = callback;
   if (!screen_saver_update_callback_.is_null() && !screen_saver_path_.empty()) {
     BrowserThread::PostTask(
         BrowserThread::UI, FROM_HERE,
         base::Bind(screen_saver_update_callback_, screen_saver_path_));
   }
 }
 
-void AppPackUpdater::Observe(int type,
-                             const content::NotificationSource& source,
-                             const content::NotificationDetails& details) {
-  switch (type) {
-    case chrome::NOTIFICATION_SYSTEM_SETTING_CHANGED:
-      DCHECK_EQ(chromeos::kAppPack,
-                *content::Details<const std::string>(details).ptr());
-      if (install_attributes_->GetMode() == DEVICE_MODE_RETAIL_KIOSK)
-        LoadPolicy();
-      break;
-
-    default:
-      NOTREACHED();
-  }
+void AppPackUpdater::AppPackChanged() {
+  if (install_attributes_->GetMode() == DEVICE_MODE_RETAIL_KIOSK)
+    LoadPolicy();
 }
 
 void AppPackUpdater::LoadPolicy() {
   chromeos::CrosSettings* settings = chromeos::CrosSettings::Get();
   if (chromeos::CrosSettingsProvider::TRUSTED != settings->PrepareTrustedValues(
           base::Bind(&AppPackUpdater::LoadPolicy,
                      weak_ptr_factory_.GetWeakPtr()))) {
     return;
   }
 
@@ skipping 74 matching lines @@
 void AppPackUpdater::SetScreenSaverPath(const base::FilePath& path) {
   // Don't invoke the callback if the path isn't changing.
   if (path != screen_saver_path_) {
     screen_saver_path_ = path;
     if (!screen_saver_update_callback_.is_null())
       screen_saver_update_callback_.Run(screen_saver_path_);
   }
 }
 
 }  // namespace policy