Fix potential crashes in NetworkHandler code

chromeos/network/network_handler.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 "chromeos/network/network_handler.h"
 
 #include "base/thread_task_runner_handle.h"
 #include "base/threading/worker_pool.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/network/auto_connect_handler.h"
@@ skipping 32 matching lines @@
     network_cert_migrator_.reset(new NetworkCertMigrator());
     client_cert_resolver_.reset(new ClientCertResolver());
   }
   network_activation_handler_.reset(new NetworkActivationHandler());
   network_connection_handler_.reset(new NetworkConnectionHandler());
   network_sms_handler_.reset(new NetworkSmsHandler());
   geolocation_handler_.reset(new GeolocationHandler());
 }
 
 NetworkHandler::~NetworkHandler() {
+  network_state_handler_->Shutdown();
 }
 
 void NetworkHandler::Init() {
   network_state_handler_->InitShillPropertyHandler();
   network_device_handler_->Init(network_state_handler_.get());
   network_profile_handler_->Init();
   network_configuration_handler_->Init(network_state_handler_.get(),
                                        network_device_handler_.get());
   managed_network_configuration_handler_->Init(
       network_state_handler_.get(), network_profile_handler_.get(),
@@ skipping 84 matching lines @@
 GeolocationHandler* NetworkHandler::geolocation_handler() {
   return geolocation_handler_.get();
 }
 
 ProhibitedTechnologiesHandler*
 NetworkHandler::prohibited_technologies_handler() {
   return prohibited_technologies_handler_.get();
 }
 
 }  // namespace chromeos