Inject JSON parsing in WebResource as a callback rather than inheritance

chrome/browser/web_resource/promo_resource_service.cc

 // Copyright (c) 2012 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/web_resource/promo_resource_service.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/location.h"
 #include "base/prefs/pref_registry_simple.h"
@@ skipping 64 matching lines @@
   registry->RegisterStringPref(prefs::kNtpPromoResourceCacheUpdate, "0");
   NotificationPromo::RegisterProfilePrefs(registry);
 }
 
 // static
 void PromoResourceService::MigrateUserPrefs(PrefService* user_prefs) {
   user_prefs->ClearPref(prefs::kNtpPromoResourceCacheUpdate);
   NotificationPromo::MigrateUserPrefs(user_prefs);
 }
 
-PromoResourceService::PromoResourceService(PrefService* local_state,
-                                           version_info::Channel channel)
-    : ChromeWebResourceService(local_state,
-                               GetPromoResourceURL(channel),
-                               true,  // append locale to URL
-                               prefs::kNtpPromoResourceCacheUpdate,
-                               kStartResourceFetchDelay,
-                               GetCacheUpdateDelay()),
+PromoResourceService::PromoResourceService(
+    PrefService* local_state,
+    version_info::Channel channel,
+    const std::string& application_locale,
+    net::URLRequestContextGetter* request_context,
+    const char* disable_network_switch,
+    const ParseJSONCallback& parse_json_callback)
+    : web_resource::WebResourceService(
+          local_state,
+          GetPromoResourceURL(channel),
+          application_locale,  // append locale to URL
+          prefs::kNtpPromoResourceCacheUpdate,
+          kStartResourceFetchDelay,
+          GetCacheUpdateDelay(),
+          request_context,
+          disable_network_switch,
+          parse_json_callback),
       weak_ptr_factory_(this) {
   ScheduleNotificationOnInit();
 }
 
 PromoResourceService::~PromoResourceService() {
 }
 
 scoped_ptr<PromoResourceService::StateChangedSubscription>
 PromoResourceService::RegisterStateChangedCallback(
     const base::Closure& closure) {
@@ skipping 64 matching lines @@
 }
 
 void PromoResourceService::Unpack(const base::DictionaryValue& parsed_json) {
   for (size_t i = 0; i < arraysize(kValidPromoTypes); ++i) {
     NotificationPromo notification_promo(prefs_);
     notification_promo.InitFromJson(parsed_json, kValidPromoTypes[i]);
     if (notification_promo.new_notification())
       ScheduleNotification(notification_promo);
   }
 }