Refactor sync-specific parts out of SyncNotifier/SyncNotifierObserver

chrome/browser/sync/glue/chrome_sync_notification_bridge.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/sync/glue/chrome_sync_notification_bridge.h"
 
 #include "base/bind.h"
 #include "base/location.h"
-#include "base/observer_list.h"
 #include "chrome/common/chrome_notification_types.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
+#include "sync/notifier/sync_notifier_helper.h"
 #include "sync/notifier/sync_notifier_observer.h"
 
 using content::BrowserThread;
 
 namespace browser_sync {
 
 class ChromeSyncNotificationBridge::Core
     : public base::RefCountedThreadSafe<Core> {
  public:
   // Created on UI thread.
   explicit Core(
       const scoped_refptr<base::SequencedTaskRunner>& sync_task_runner);
 
   // All member functions below must be called on the sync task runner.
 
   void UpdateEnabledTypes(syncer::ModelTypeSet enabled_types);
-  void AddObserver(syncer::SyncNotifierObserver* observer);
-  void RemoveObserver(syncer::SyncNotifierObserver* observer);
+  void UpdateRegisteredIds(syncer::SyncNotifierObserver* handler,
+                           const syncer::ObjectIdSet& ids);
 
   void EmitNotification(
       const syncer::ModelTypePayloadMap& payload_map,
       syncer::IncomingNotificationSource notification_source);
 
  private:
   friend class base::RefCountedThreadSafe<Core>;
 
   // Destroyed on the UI thread or on |sync_task_runner_|.
   ~Core();
 
   const scoped_refptr<base::SequencedTaskRunner> sync_task_runner_;
 
   // Used only on |sync_task_runner_|.
   syncer::ModelTypeSet enabled_types_;
-  ObserverList<syncer::SyncNotifierObserver> observers_;
+  syncer::SyncNotifierHelper helper_;
 };
 
 ChromeSyncNotificationBridge::Core::Core(
     const scoped_refptr<base::SequencedTaskRunner>& sync_task_runner)
     : sync_task_runner_(sync_task_runner) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(sync_task_runner_.get());
 }
 
 ChromeSyncNotificationBridge::Core::~Core() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI) ||
          sync_task_runner_->RunsTasksOnCurrentThread());
 }
 
 void ChromeSyncNotificationBridge::Core::UpdateEnabledTypes(
     syncer::ModelTypeSet types) {
   DCHECK(sync_task_runner_->RunsTasksOnCurrentThread());
   enabled_types_ = types;
 }
 
-void ChromeSyncNotificationBridge::Core::AddObserver(
-    syncer::SyncNotifierObserver* observer) {
+void ChromeSyncNotificationBridge::Core::UpdateRegisteredIds(
+    syncer::SyncNotifierObserver* handler,
+    const syncer::ObjectIdSet& ids) {
   DCHECK(sync_task_runner_->RunsTasksOnCurrentThread());
-  observers_.AddObserver(observer);
-}
-
-void ChromeSyncNotificationBridge::Core::RemoveObserver(
-    syncer::SyncNotifierObserver* observer) {
-  DCHECK(sync_task_runner_->RunsTasksOnCurrentThread());
-  observers_.RemoveObserver(observer);
+  helper_.UpdateRegisteredIds(handler, ids);
 }
 
 void ChromeSyncNotificationBridge::Core::EmitNotification(
     const syncer::ModelTypePayloadMap& payload_map,
     syncer::IncomingNotificationSource notification_source) {
   DCHECK(sync_task_runner_->RunsTasksOnCurrentThread());
   const syncer::ModelTypePayloadMap& effective_payload_map =
       payload_map.empty() ?
       syncer::ModelTypePayloadMapFromEnumSet(enabled_types_, std::string()) :
       payload_map;
 
-  FOR_EACH_OBSERVER(
-      syncer::SyncNotifierObserver, observers_,
-      OnIncomingNotification(effective_payload_map, notification_source));
+  helper_.DispatchInvalidationsToHandlers(
+      ModelTypePayloadMapToObjectIdPayloadMap(effective_payload_map),
+      notification_source);
 }
 
 ChromeSyncNotificationBridge::ChromeSyncNotificationBridge(
     const Profile* profile,
     const scoped_refptr<base::SequencedTaskRunner>& sync_task_runner)
     : sync_task_runner_(sync_task_runner),
       core_(new Core(sync_task_runner_)) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(profile);
   registrar_.Add(this, chrome::NOTIFICATION_SYNC_REFRESH_LOCAL,
                  content::Source<Profile>(profile));
   registrar_.Add(this, chrome::NOTIFICATION_SYNC_REFRESH_REMOTE,
                  content::Source<Profile>(profile));
 }
 
 ChromeSyncNotificationBridge::~ChromeSyncNotificationBridge() {}
 
 void ChromeSyncNotificationBridge::UpdateEnabledTypes(
     syncer::ModelTypeSet types) {
   DCHECK(sync_task_runner_->RunsTasksOnCurrentThread());
   core_->UpdateEnabledTypes(types);
 }
 
-void ChromeSyncNotificationBridge::AddObserver(
-    syncer::SyncNotifierObserver* observer) {
+void ChromeSyncNotificationBridge::UpdateRegisteredIds(
+    syncer::SyncNotifierObserver* handler,
+    const syncer::ObjectIdSet& ids) {
   DCHECK(sync_task_runner_->RunsTasksOnCurrentThread());
-  core_->AddObserver(observer);
-}
-
-void ChromeSyncNotificationBridge::RemoveObserver(
-    syncer::SyncNotifierObserver* observer) {
-  DCHECK(sync_task_runner_->RunsTasksOnCurrentThread());
-  core_->RemoveObserver(observer);
+  core_->UpdateRegisteredIds(handler, ids);
 }
 
 void ChromeSyncNotificationBridge::Observe(
     int type,
     const content::NotificationSource& source,
     const content::NotificationDetails& details) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   syncer::IncomingNotificationSource notification_source;
   if (type == chrome::NOTIFICATION_SYNC_REFRESH_LOCAL) {
     notification_source = syncer::LOCAL_NOTIFICATION;
   } else if (type == chrome::NOTIFICATION_SYNC_REFRESH_REMOTE) {
     notification_source = syncer::REMOTE_NOTIFICATION;
   } else {
     NOTREACHED() << "Unexpected notification type: " << type;
     return;
   }
 
   content::Details<const syncer::ModelTypePayloadMap>
       payload_details(details);
   const syncer::ModelTypePayloadMap& payload_map = *(payload_details.ptr());
   sync_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&Core::EmitNotification,
                  core_, payload_map, notification_source));
 }
 
 }  // namespace browser_sync