Reduce FOR_EACH_OBSERVER usage in extensions

extensions/browser/api/networking_private/networking_private_service_client.cc

 // Copyright 2013 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 "extensions/browser/api/networking_private/networking_private_service_client.h"
 
 #include "base/base64.h"
 #include "base/bind.h"
 #include "base/sequenced_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
@@ skipping 441 matching lines @@
   } else {
     DCHECK(!service_callbacks->start_disconnect_callback.is_null());
     service_callbacks->start_disconnect_callback.Run();
   }
   RemoveServiceCallbacks(callback_id);
 }
 
 void NetworkingPrivateServiceClient::OnNetworksChangedEventOnUIThread(
     const std::vector<std::string>& network_guids) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  FOR_EACH_OBSERVER(NetworkingPrivateDelegateObserver,
-                    network_events_observers_,
-                    OnNetworksChangedEvent(network_guids));
+  for (auto& observer : network_events_observers_)
+    observer.OnNetworksChangedEvent(network_guids);
 }
 
 void NetworkingPrivateServiceClient::OnNetworkListChangedEventOnUIThread(
     const std::vector<std::string>& network_guids) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  FOR_EACH_OBSERVER(NetworkingPrivateDelegateObserver,
-                    network_events_observers_,
-                    OnNetworkListChangedEvent(network_guids));
+  for (auto& observer : network_events_observers_)
+    observer.OnNetworkListChangedEvent(network_guids);
 }
 
 }  // namespace extensions