[ObjC ARC] Converts ios/chrome/browser/ui/sync:sync to ARC.

ios/chrome/browser/ui/sync/sync_error_infobar_delegate.mm

 // 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.
 
 #include "ios/chrome/browser/ui/sync/sync_error_infobar_delegate.h"
 
 #import <UIKit/UIKit.h>
 
 #include <utility>
 
 #include "base/logging.h"
-#include "base/mac/scoped_nsobject.h"
 #include "base/memory/ptr_util.h"
 #include "base/strings/sys_string_conversions.h"
 #include "components/browser_sync/profile_sync_service.h"
 #include "components/infobars/core/infobar.h"
 #include "components/infobars/core/infobar_delegate.h"
 #include "components/infobars/core/infobar_manager.h"
 #include "components/sync/driver/sync_service.h"
 #import "ios/chrome/browser/browser_state/chrome_browser_state.h"
 #include "ios/chrome/browser/sync/ios_chrome_profile_sync_service_factory.h"
 #include "ios/chrome/browser/sync/sync_setup_service.h"
 #include "ios/chrome/browser/sync/sync_setup_service_factory.h"
 #import "ios/chrome/browser/ui/commands/UIKit+ChromeExecuteCommand.h"
 #import "ios/chrome/browser/ui/commands/generic_chrome_command.h"
 #import "ios/chrome/browser/ui/sync/sync_util.h"
 #include "ui/base/l10n/l10n_util.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 // static
 bool SyncErrorInfoBarDelegate::Create(infobars::InfoBarManager* infobar_manager,
                                       ios::ChromeBrowserState* browser_state) {
   DCHECK(infobar_manager);
   std::unique_ptr<ConfirmInfoBarDelegate> delegate(
       new SyncErrorInfoBarDelegate(browser_state));
   return !!infobar_manager->AddInfoBar(
       infobar_manager->CreateConfirmInfoBar(std::move(delegate)));
 }
 
 SyncErrorInfoBarDelegate::SyncErrorInfoBarDelegate(
     ios::ChromeBrowserState* browser_state)
     : browser_state_(browser_state) {
   DCHECK(!browser_state->IsOffTheRecord());
   icon_ = gfx::Image([UIImage imageNamed:@"infobar_warning"]);
   SyncSetupService* sync_setup_service =
       SyncSetupServiceFactory::GetForBrowserState(browser_state);
   DCHECK(sync_setup_service);
   // Set all of the UI based on the sync state at the same time to ensure
   // they all correspond to the same sync error.
   error_state_ = sync_setup_service->GetSyncServiceState();
   message_ = base::SysNSStringToUTF16(
       ios_internal::sync::GetSyncErrorMessageForBrowserState(browser_state_));
   button_text_ = base::SysNSStringToUTF16(
       ios_internal::sync::GetSyncErrorButtonTitleForBrowserState(
           browser_state_));
-  command_.reset([ios_internal::sync::GetSyncCommandForBrowserState(
-      browser_state_) retain]);
+  command_.reset(
+      ios_internal::sync::GetSyncCommandForBrowserState(browser_state_));
 
   // Register for sync status changes.
   syncer::SyncService* sync_service =
       IOSChromeProfileSyncServiceFactory::GetForBrowserState(browser_state_);
   sync_service->AddObserver(this);
 }
 
 SyncErrorInfoBarDelegate::~SyncErrorInfoBarDelegate() {
   syncer::SyncService* sync_service =
       IOSChromeProfileSyncServiceFactory::GetForBrowserState(browser_state_);
@@ skipping 49 matching lines @@
     infobars::InfoBarManager* infobar_manager = infobar->owner();
     if (infobar_manager) {
       std::unique_ptr<ConfirmInfoBarDelegate> new_infobar_delegate(
           new SyncErrorInfoBarDelegate(browser_state_));
       infobar_manager->ReplaceInfoBar(infobar,
                                       infobar_manager->CreateConfirmInfoBar(
                                           std::move(new_infobar_delegate)));
     }
   }
 }