Solve ProfileIOData, Extension, HostContentSettingsMap ordering issue.

chrome/browser/content_settings/host_content_settings_map_factory.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/content_settings/host_content_settings_map_factory.h"
 
 #include <utility>
 
 #include "base/feature_list.h"
 #include "chrome/browser/prefs/pref_service_syncable_util.h"
@@ skipping 75 matching lines @@
 
   sync_preferences::PrefServiceSyncable* pref_service =
       PrefServiceSyncableFromProfile(profile);
   if (pref_service) {
     pref_service->RegisterMergeDataFinishedCallback(
         base::Bind(&HostContentSettingsMap::MigrateDomainScopedSettings,
                    settings_map->GetWeakPtr(), true /* after_sync */));
   }
 
 #if BUILDFLAG(ENABLE_EXTENSIONS)
-  ExtensionService *ext_service =
-      extensions::ExtensionSystem::Get(profile)->extension_service();
-  // This may be null in testing or when the extenion_service hasn't been
-  // initialized, in which case it will be registered then.
-  if (ext_service)
-    ext_service->RegisterContentSettings(settings_map.get());
+  // These must be registered before before the HostSettings are passed over to
+  // the IOThread.  Simplest to do this on construction.
+  ExtensionService::RegisterContentSettings(settings_map.get(), profile);
 #endif // BUILDFLAG(ENABLE_EXTENSIONS)
 #if BUILDFLAG(ENABLE_SUPERVISED_USERS)
   SupervisedUserSettingsService* supervised_service =
       SupervisedUserSettingsServiceFactory::GetForProfile(profile);
   // This may be null in testing.
   if (supervised_service) {
     std::unique_ptr<content_settings::SupervisedProvider> supervised_provider(
         new content_settings::SupervisedProvider(supervised_service));
     settings_map->RegisterProvider(HostContentSettingsMap::SUPERVISED_PROVIDER,
                                    std::move(supervised_provider));
   }
 #endif // BUILDFLAG(ENABLE_SUPERVISED_USERS)
 
   return settings_map;
 }
 
 content::BrowserContext* HostContentSettingsMapFactory::GetBrowserContextToUse(
     content::BrowserContext* context) const {
   return context;
 }