[ObjC ARC] Converts ios/chrome/browser/web:web_internal to ARC.

ios/chrome/browser/web/blocked_popup_tab_helper.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.
 
 #import "ios/chrome/browser/web/blocked_popup_tab_helper.h"
 
 #include <UIKit/UIKit.h>
 
 #include <memory>
 #include <utility>
 
 #include "base/format_macros.h"
 #include "base/mac/bundle_locations.h"
 #include "base/mac/foundation_util.h"
 #include "base/memory/ptr_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "components/content_settings/core/browser/host_content_settings_map.h"
 #include "components/infobars/core/confirm_infobar_delegate.h"
 #include "components/infobars/core/infobar.h"
 #include "ios/chrome/browser/browser_state/chrome_browser_state.h"
 #include "ios/chrome/browser/content_settings/host_content_settings_map_factory.h"
 #include "ios/chrome/browser/infobars/infobar_manager_impl.h"
 #include "ios/chrome/grit/ios_strings.h"
 #include "ios/web/public/referrer.h"
 #include "net/base/mac/url_conversions.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/image/image.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 DEFINE_WEB_STATE_USER_DATA_KEY(BlockedPopupTabHelper);
 
 namespace {
 // The infobar to display when a popup is blocked.
 class BlockPopupInfoBarDelegate : public ConfirmInfoBarDelegate {
  public:
   BlockPopupInfoBarDelegate(
       ios::ChromeBrowserState* browser_state,
       web::WebState* web_state,
       const std::vector<BlockedPopupTabHelper::Popup>& popups)
@@ skipping 119 matching lines @@
   DCHECK(infobar_manager);
 
   if (scoped_observer_.IsObserving(infobar_manager)) {
     return;
   }
 
   // Verify that this object is never observing more than one InfoBarManager.
   DCHECK(!scoped_observer_.IsObservingSources());
   scoped_observer_.Add(infobar_manager);
 }