Fixed nullptr default network crash.

chrome/browser/chromeos/arc/arc_settings_service.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/chromeos/arc/arc_settings_service.h"
 
 #include <string>
 
 #include "base/gtest_prod_util.h"
 #include "base/json/json_writer.h"
@@ skipping 458 matching lines @@
   instance->SendBroadcast(action, "org.chromium.arc.intent_helper",
                           "org.chromium.arc.intent_helper.SettingsReceiver",
                           extras_json);
 }
 
 void ArcSettingsServiceImpl::DefaultNetworkChanged(
     const chromeos::NetworkState* network) {
   // kProxy pref and ONC policy have more priority than the default network
   // update.
   Profile* profile = ProfileManager::GetActiveUserProfile();
-  if (!chromeos::onc::HasPolicyForNetwork(
-          profile->GetPrefs(), g_browser_process->local_state(), *network) &&
-      !IsPrefProxyConfigApplied()) {
+  if (network && !IsPrefProxyConfigApplied() &&
+      !chromeos::onc::HasPolicyForNetwork(
+          profile->GetPrefs(), g_browser_process->local_state(), *network)) {
     SyncProxySettings();
   }
 }
 
 ArcSettingsService::ArcSettingsService(ArcBridgeService* bridge_service)
     : ArcService(bridge_service) {
   arc_bridge_service()->intent_helper()->AddObserver(this);
 }
 
 ArcSettingsService::~ArcSettingsService() {
   arc_bridge_service()->intent_helper()->RemoveObserver(this);
 }
 
 void ArcSettingsService::OnInstanceReady() {
   impl_.reset(new ArcSettingsServiceImpl(arc_bridge_service()));
 }
 
 void ArcSettingsService::OnInstanceClosed() {
   impl_.reset();
 }
 
 }  // namespace arc