Convert //ios from scoped_ptr to std::unique_ptr.

ios/chrome/browser/sync/ios_chrome_sync_client.h

Index: ios/chrome/browser/sync/ios_chrome_sync_client.h
diff --git a/ios/chrome/browser/sync/ios_chrome_sync_client.h b/ios/chrome/browser/sync/ios_chrome_sync_client.h
index 3708fdffe97ba2097794e2dde80d8c3ffb98d4c3..082d24911325d9829caf1797f6004033860f431b 100644
--- a/ios/chrome/browser/sync/ios_chrome_sync_client.h
+++ b/ios/chrome/browser/sync/ios_chrome_sync_client.h
@@ -59,7 +59,7 @@ class IOSChromeSyncClient : public sync_driver::SyncClient {
   sync_driver::SyncApiComponentFactory* GetSyncApiComponentFactory() override;
 
   void SetSyncApiComponentFactoryForTesting(
-      scoped_ptr<sync_driver::SyncApiComponentFactory> component_factory);
+      std::unique_ptr<sync_driver::SyncApiComponentFactory> component_factory);
 
   // Iterates over browser states and returns any trackers that can be found.
   static void GetDeviceInfoTrackers(
@@ -69,14 +69,14 @@ class IOSChromeSyncClient : public sync_driver::SyncClient {
   ios::ChromeBrowserState* const browser_state_;
 
   // The sync api component factory in use by this client.
-  scoped_ptr<sync_driver::SyncApiComponentFactory> component_factory_;
+  std::unique_ptr<sync_driver::SyncApiComponentFactory> component_factory_;
 
   // Members that must be fetched on the UI thread but accessed on their
   // respective backend threads.
   scoped_refptr<autofill::AutofillWebDataService> web_data_service_;
   scoped_refptr<password_manager::PasswordStore> password_store_;
 
-  scoped_ptr<sync_sessions::SyncSessionsClient> sync_sessions_client_;
+  std::unique_ptr<sync_sessions::SyncSessionsClient> sync_sessions_client_;
 
   const scoped_refptr<syncer::ExtensionsActivity> dummy_extensions_activity_;