[Sync] Move ModelType and related classes to 'syncer' namespace

sync/notifier/non_blocking_invalidation_notifier.h

Index: sync/notifier/non_blocking_invalidation_notifier.h
diff --git a/sync/notifier/non_blocking_invalidation_notifier.h b/sync/notifier/non_blocking_invalidation_notifier.h
index e953c3c3102155c7a091ae6d8335396456c2830f..8c2cfafee40b8ef5fede696b29af0bba95752dfc 100644
--- a/sync/notifier/non_blocking_invalidation_notifier.h
+++ b/sync/notifier/non_blocking_invalidation_notifier.h
@@ -52,16 +52,16 @@ class NonBlockingInvalidationNotifier
   virtual void UpdateCredentials(
       const std::string& email, const std::string& token) OVERRIDE;
   virtual void UpdateEnabledTypes(
-      syncable::ModelTypeSet enabled_types) OVERRIDE;
+      syncer::ModelTypeSet enabled_types) OVERRIDE;
   virtual void SendNotification(
-      syncable::ModelTypeSet changed_types) OVERRIDE;
+      syncer::ModelTypeSet changed_types) OVERRIDE;
 
   // SyncNotifierObserver implementation.
   virtual void OnNotificationsEnabled() OVERRIDE;
   virtual void OnNotificationsDisabled(
       NotificationsDisabledReason reason) OVERRIDE;
   virtual void OnIncomingNotification(
-      const syncable::ModelTypePayloadMap& type_payloads,
+      const syncer::ModelTypePayloadMap& type_payloads,
       IncomingNotificationSource source) OVERRIDE;
 
  private: