[Sync] Pass ModelTypeSet by value everywhere

sync/internal_api/public/sync_manager.h

 // 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.
 
 #ifndef SYNC_INTERNAL_API_PUBLIC_SYNC_MANAGER_H_
 #define SYNC_INTERNAL_API_PUBLIC_SYNC_MANAGER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 321 matching lines @@
 
   // Purge from the directory those types with non-empty progress markers
   // but without initial synced ended set.
   // Returns false if an error occurred, true otherwise.
   virtual bool PurgePartiallySyncedTypes() = 0;
 
   // Update tokens that we're using in Sync. Email must stay the same.
   virtual void UpdateCredentials(const SyncCredentials& credentials) = 0;
 
   // Called when the user disables or enables a sync type.
-  virtual void UpdateEnabledTypes(
-      const ModelTypeSet& enabled_types) = 0;
+  virtual void UpdateEnabledTypes(ModelTypeSet enabled_types) = 0;
 
   // Forwards to the underlying invalidator (see comments in invalidator.h).
   virtual void RegisterInvalidationHandler(
       InvalidationHandler* handler) = 0;
 
   // Forwards to the underlying notifier (see comments in invalidator.h).
   virtual void UpdateRegisteredInvalidationIds(
       InvalidationHandler* handler,
       const ObjectIdSet& ids) = 0;
 
   // Forwards to the underlying notifier (see comments in invalidator.h).
   virtual void UnregisterInvalidationHandler(
       InvalidationHandler* handler) = 0;
 
   // Put the syncer in normal mode ready to perform nudges and polls.
   virtual void StartSyncingNormally(
       const ModelSafeRoutingInfo& routing_info) = 0;
 
   // Switches the mode of operation to CONFIGURATION_MODE and performs
   // any configuration tasks needed as determined by the params. Once complete,
   // syncer will remain in CONFIGURATION_MODE until StartSyncingNormally is
   // called.
   // |ready_task| is invoked when the configuration completes.
   // |retry_task| is invoked if the configuration job could not immediately
   //              execute. |ready_task| will still be called when it eventually
   //              does finish.
   virtual void ConfigureSyncer(
       ConfigureReason reason,
-      const ModelTypeSet& types_to_config,
+      ModelTypeSet types_to_config,
       const ModelSafeRoutingInfo& new_routing_info,
       const base::Closure& ready_task,
       const base::Closure& retry_task) = 0;
 
   // Adds a listener to be notified of sync events.
   // NOTE: It is OK (in fact, it's probably a good idea) to call this before
   // having received OnInitializationCompleted.
   virtual void AddObserver(Observer* observer) = 0;
 
   // Remove the given observer.  Make sure to call this if the
@@ skipping 34 matching lines @@
   // any remaining unsynced items.  May be called on any thread.
   virtual bool HasUnsyncedItems() = 0;
 
   // Returns the SyncManager's encryption handler.
   virtual SyncEncryptionHandler* GetEncryptionHandler() = 0;
 };
 
 }  // namespace syncer
 
 #endif  // SYNC_INTERNAL_API_PUBLIC_SYNC_MANAGER_H_