Pass args to SyncManager::Init via a struct.

sync/internal_api/sync_backup_manager.h

Index: sync/internal_api/sync_backup_manager.h
diff --git a/sync/internal_api/sync_backup_manager.h b/sync/internal_api/sync_backup_manager.h
index a065c877125b8c80f4c595d0496079704426d7bb..f8fa1aa6cc9aa4002ef96d3afef0866acaf2eabb 100644
--- a/sync/internal_api/sync_backup_manager.h
+++ b/sync/internal_api/sync_backup_manager.h
@@ -21,23 +21,7 @@ class SYNC_EXPORT_PRIVATE SyncBackupManager : public SyncRollbackManagerBase {
   virtual ~SyncBackupManager();
 
   // SyncManager implementation.
-  virtual void Init(
-      const base::FilePath& database_location,
-      const WeakHandle<JsEventHandler>& event_handler,
-      const GURL& service_url,
-      scoped_ptr<HttpPostProviderFactory> post_factory,
-      const std::vector<scoped_refptr<ModelSafeWorker> >& workers,
-      ExtensionsActivity* extensions_activity,
-      SyncManager::ChangeDelegate* change_delegate,
-      const SyncCredentials& credentials,
-      const std::string& invalidator_client_id,
-      const std::string& restored_key_for_bootstrapping,
-      const std::string& restored_keystore_key_for_bootstrapping,
-      InternalComponentsFactory* internal_components_factory,
-      Encryptor* encryptor,
-      scoped_ptr<UnrecoverableErrorHandler> unrecoverable_error_handler,
-      ReportUnrecoverableErrorFunction report_unrecoverable_error_function,
-      CancelationSignal* cancelation_signal) OVERRIDE;
+  virtual void Init(InitArgs* args) OVERRIDE;
   virtual void SaveChanges() OVERRIDE;
   virtual SyncStatus GetDetailedStatus() const OVERRIDE;