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

ios/chrome/browser/sync/sessions/ios_chrome_local_session_event_router.h

 // Copyright 2015 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_SESSIONS_IOS_CHROME_LOCAL_EVENT_SESSION_ROUTER_H_
 #define IOS_CHROME_BROWSER_SYNC_SESSIONS_IOS_CHROME_LOCAL_EVENT_SESSION_ROUTER_H_
 
 #include <stddef.h>
 
 #include <set>
@@ skipping 54 matching lines @@
   // http://www.google.com/favicon.ico) have changed. It is valid to call
   // OnFaviconsChanged() with non-empty |page_urls| and an empty |icon_url|
   // and vice versa.
   void OnFaviconsChanged(const std::set<GURL>& page_urls, const GURL& icon_url);
 
   browser_sync::LocalSessionEventHandler* handler_;
   ios::ChromeBrowserState* const browser_state_;
   sync_sessions::SyncSessionsClient* const sessions_client_;
   syncer::SyncableService::StartSyncFlare flare_;
 
-  scoped_ptr<base::CallbackList<void(const std::set<GURL>&,
-                                     const GURL&)>::Subscription>
+  std::unique_ptr<base::CallbackList<void(const std::set<GURL>&,
+                                          const GURL&)>::Subscription>
       favicon_changed_subscription_;
 
-  scoped_ptr<base::CallbackList<void(web::WebState*)>::Subscription>
+  std::unique_ptr<base::CallbackList<void(web::WebState*)>::Subscription>
       tab_parented_subscription_;
 
   DISALLOW_COPY_AND_ASSIGN(IOSChromeLocalSessionEventRouter);
 };
 
 #endif  // IOS_CHROME_BROWSER_SYNC_SESSIONS_IOS_CHROME_LOCAL_EVENT_SESSION_ROUTER_H_