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

ios/chrome/browser/infobars/infobar_manager_impl.mm

 // Copyright 2014 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.
 
 #include "ios/chrome/browser/infobars/infobar_manager_impl.h"
 
 #include <utility>
 
 #include "components/infobars/core/confirm_infobar_delegate.h"
 #include "components/infobars/core/infobar.h"
@@ skipping 44 matching lines @@
 InfoBarManagerImpl::~InfoBarManagerImpl() {
   ShutDown();
 }
 
 int InfoBarManagerImpl::GetActiveEntryID() {
   web::NavigationItem* visible_item =
       web_state()->GetNavigationManager()->GetVisibleItem();
   return visible_item ? visible_item->GetUniqueID() : 0;
 }
 
-scoped_ptr<infobars::InfoBar> InfoBarManagerImpl::CreateConfirmInfoBar(
-    scoped_ptr<ConfirmInfoBarDelegate> delegate) {
+std::unique_ptr<infobars::InfoBar> InfoBarManagerImpl::CreateConfirmInfoBar(
+    std::unique_ptr<ConfirmInfoBarDelegate> delegate) {
   return ::CreateConfirmInfoBar(std::move(delegate));
 }
 
 void InfoBarManagerImpl::NavigationItemCommitted(
     const web::LoadCommittedDetails& load_details) {
   OnNavigation(NavigationDetailsFromLoadCommittedDetails(load_details));
 }
 
 void InfoBarManagerImpl::WebStateDestroyed() {
   // The WebState is going away; be aggressively paranoid and delete this
   // InfoBarManagerImpl lest other parts of the system attempt to add infobars
   // or use it otherwise during the destruction.
   web_state()->RemoveUserData(UserDataKey());
   // That was the equivalent of "delete this". This object is now destroyed;
   // returning from this function is the only safe thing to do.
 }
 
 void InfoBarManagerImpl::OpenURL(const GURL& url,
                                  WindowOpenDisposition disposition) {
   NOTIMPLEMENTED();
 }