Refactor sync-specific parts out of SyncNotifier/SyncNotifierObserver

sync/notifier/p2p_notifier.cc

Index: sync/notifier/p2p_notifier.cc
diff --git a/sync/notifier/p2p_notifier.cc b/sync/notifier/p2p_notifier.cc
index e2a4209bfdd3b8bd0d363df1978a36cf97b97e36..9d1bd1a37a1d0601b75837427eb83e0f979bc6a3 100644
--- a/sync/notifier/p2p_notifier.cc
+++ b/sync/notifier/p2p_notifier.cc
@@ -12,6 +12,7 @@
 #include "base/values.h"
 #include "jingle/notifier/listener/push_client.h"
 #include "sync/internal_api/public/base/model_type_payload_map.h"
+#include "sync/notifier/invalidation_util.h"
 #include "sync/notifier/sync_notifier_observer.h"
 
 namespace syncer {
@@ -156,14 +157,16 @@ P2PNotifier::~P2PNotifier() {
   push_client_->RemoveObserver(this);
 }
 
-void P2PNotifier::AddObserver(SyncNotifierObserver* observer) {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  observer_list_.AddObserver(observer);
-}
-
-void P2PNotifier::RemoveObserver(SyncNotifierObserver* observer) {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  observer_list_.RemoveObserver(observer);
+void P2PNotifier::UpdateRegisteredIds(SyncNotifierObserver* handler,
+                                      const ObjectIdSet& ids) {
+  const ModelTypeSet& enabled_types = ObjectIdSetToModelTypeSet(
+      helper_.UpdateRegisteredIds(handler, ids));
+  const ModelTypeSet& new_enabled_types =
+      Difference(enabled_types, enabled_types_);
+  const P2PNotificationData notification_data(
+      unique_id_, NOTIFY_SELF, new_enabled_types);
+  SendNotificationData(notification_data);
+  enabled_types_ = enabled_types;
 }
 
 void P2PNotifier::SetUniqueId(const std::string& unique_id) {
@@ -193,16 +196,6 @@ void P2PNotifier::UpdateCredentials(
   logged_in_ = true;
 }
 
-void P2PNotifier::UpdateEnabledTypes(ModelTypeSet enabled_types) {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  const ModelTypeSet new_enabled_types =
-      Difference(enabled_types, enabled_types_);
-  enabled_types_ = enabled_types;
-  const P2PNotificationData notification_data(
-      unique_id_, NOTIFY_SELF, new_enabled_types);
-  SendNotificationData(notification_data);
-}
-
 void P2PNotifier::SendNotification(ModelTypeSet changed_types) {
   DCHECK(thread_checker_.CalledOnValidThread());
   const P2PNotificationData notification_data(
@@ -214,9 +207,7 @@ void P2PNotifier::OnNotificationsEnabled() {
   DCHECK(thread_checker_.CalledOnValidThread());
   bool just_turned_on = (notifications_enabled_ == false);
   notifications_enabled_ = true;
-  FOR_EACH_OBSERVER(
-      SyncNotifierObserver, observer_list_,
-      OnNotificationsEnabled());
+  helper_.EmitOnNotificationsEnabled();
   if (just_turned_on) {
     const P2PNotificationData notification_data(
         unique_id_, NOTIFY_SELF, enabled_types_);
@@ -227,9 +218,7 @@ void P2PNotifier::OnNotificationsEnabled() {
 void P2PNotifier::OnNotificationsDisabled(
     notifier::NotificationsDisabledReason reason) {
   DCHECK(thread_checker_.CalledOnValidThread());
-  FOR_EACH_OBSERVER(
-      SyncNotifierObserver, observer_list_,
-      OnNotificationsDisabled(FromNotifierReason(reason)));
+  helper_.EmitOnNotificationsDisabled(FromNotifierReason(reason));
 }
 
 void P2PNotifier::OnIncomingNotification(
@@ -264,11 +253,11 @@ void P2PNotifier::OnIncomingNotification(
     DVLOG(1) << "No changed types -- not emitting notification";
     return;
   }
-  const ModelTypePayloadMap& type_payloads =
-      ModelTypePayloadMapFromEnumSet(
-          notification_data.GetChangedTypes(), std::string());
-  FOR_EACH_OBSERVER(SyncNotifierObserver, observer_list_,
-                    OnIncomingNotification(type_payloads, REMOTE_NOTIFICATION));
+  const ModelTypePayloadMap& type_payloads = ModelTypePayloadMapFromEnumSet(
+      notification_data.GetChangedTypes(), std::string());
+  helper_.DispatchInvalidationsToHandlers(
+      ModelTypePayloadMapToObjectIdPayloadMap(type_payloads),
+      REMOTE_NOTIFICATION);
 }
 
 void P2PNotifier::SendNotificationDataForTest(