Replace base::CallbackList with base::ObserverList in CastConfigDelegate

chrome/browser/ui/ash/cast_config_delegate_media_router.cc

 // Copyright 2015 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/ui/ash/cast_config_delegate_media_router.h"
 
 #include "base/macros.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/media/router/media_router.h"
@@ skipping 118 matching lines @@
     devices_->Init();
   }
 
   return devices_.get();
 }
 
 bool CastConfigDelegateMediaRouter::HasCastExtension() const {
   return true;
 }
 
-CastConfigDelegateMediaRouter::DeviceUpdateSubscription
-CastConfigDelegateMediaRouter::RegisterDeviceUpdateObserver(
-    const ReceiversAndActivitesCallback& callback) {
-  return callback_list_.Add(callback);
+void CastConfigDelegateMediaRouter::AddObserver(
+    ash::CastConfigDelegate::Observer* observer) {
+  observer_list_.AddObserver(observer);
+}
+
+void CastConfigDelegateMediaRouter::RemoveObserver(
+    ash::CastConfigDelegate::Observer* observer) {
+  observer_list_.RemoveObserver(observer);
 }
 
 void CastConfigDelegateMediaRouter::RequestDeviceRefresh() {
   // The media router component isn't ready yet.
   if (!devices())
     return;
 
   // Build the old-style ReceiverAndActivity set out of the MediaRouter
   // source/sink/route setup. We first map the existing sinks, and then we
   // update those sinks with activity information.
@@ skipping 32 matching lines @@
           item.activity.tab_id = 0;
           if (media_router::IsDesktopMirroringMediaSource(route.media_source()))
             item.activity.tab_id = Activity::TabId::DESKTOP;
         }
 
         break;
       }
     }
   }
 
-  callback_list_.Notify(items);
+  FOR_EACH_OBSERVER(ash::CastConfigDelegate::Observer, observer_list_,
+                    OnDevicesUpdated(items));
 }
 
 void CastConfigDelegateMediaRouter::CastToReceiver(
     const std::string& receiver_id) {
   GetMediaRouter()->CreateRoute(
       media_router::MediaSourceForDesktop().id(), receiver_id,
       GURL("http://cros-cast-origin/"), nullptr,
       std::vector<media_router::MediaRouteResponseCallback>());
 }
 
 void CastConfigDelegateMediaRouter::StopCasting(const std::string& route_id) {
   GetMediaRouter()->TerminateRoute(route_id);
 }
 
 bool CastConfigDelegateMediaRouter::HasOptions() const {
   // There are no plans to have an options page for the MediaRouter.
   return false;
 }
 
 void CastConfigDelegateMediaRouter::LaunchCastOptions() {}