[Sync] Replace typedef with using.

ios/chrome/browser/sync/sync_setup_service.h

 // Copyright 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 IOS_CHROME_BROWSER_SYNC_SYNC_SETUP_SERVICE_H_
 #define IOS_CHROME_BROWSER_SYNC_SYNC_SETUP_SERVICE_H_
 
 #include <map>
 #include <memory>
 
 #include "base/macros.h"
 #include "base/strings/string16.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "components/sync/base/model_type.h"
 #include "components/sync/base/syncer_error.h"
 
 class PrefService;
 
 namespace syncer {
 class SyncService;
 class SyncSetupInProgressHandle;
 }  // namespace syncer
 
 // Class that allows configuring sync. It handles enabling and disabling it, as
 // well as choosing datatypes. Most actions are delayed until a commit is done,
 // to allow the complex sync setup flow on iOS.
 class SyncSetupService : public KeyedService {
  public:
-  typedef enum {
+  using SyncServiceState = enum {
     kNoSyncServiceError,
     kSyncServiceSignInNeedsUpdate,
     kSyncServiceCouldNotConnect,
     kSyncServiceServiceUnavailable,
     kSyncServiceNeedsPassphrase,
     kSyncServiceUnrecoverableError,
     kLastSyncServiceError = kSyncServiceUnrecoverableError
-  } SyncServiceState;
+  };
 
   // The set of user-selectable datatypes handled by Chrome for iOS.
-  typedef enum {
+  using SyncableDatatype = enum {
     kSyncBookmarks,
     kSyncOmniboxHistory,
     kSyncPasswords,
     kSyncOpenTabs,
     kSyncAutofill,
     kSyncPreferences,
     kSyncReadingList,
     kNumberOfSyncableDatatypes
-  } SyncableDatatype;
+  };
 
   SyncSetupService(syncer::SyncService* sync_service, PrefService* prefs);
   ~SyncSetupService() override;
 
   // Returns the |syncer::ModelType| associated to the given
   // |SyncableDatatypes|.
   syncer::ModelType GetModelType(SyncableDatatype datatype);
 
   // Returns whether sync is enabled.
   virtual bool IsSyncEnabled() const;
@@ skipping 49 matching lines @@
   PrefService* const prefs_;
   syncer::ModelTypeSet user_selectable_types_;
 
   // Prevents Sync from running until configuration is complete.
   std::unique_ptr<syncer::SyncSetupInProgressHandle> sync_blocker_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncSetupService);
 };
 
 #endif  // IOS_CHROME_BROWSER_SYNC_SYNC_SETUP_SERVICE_H_