Convert //ios/web_view/internal to ARC.

ios/web_view/internal/criwv_web_main_parts.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.
 
 #import "ios/web_view/internal/criwv_web_main_parts.h"
 
 #include "base/base_paths.h"
 #include "base/memory/ptr_util.h"
 #include "base/path_service.h"
 #include "components/translate/core/browser/translate_download_manager.h"
 #include "ios/web_view/internal/criwv_browser_state.h"
 #import "ios/web_view/public/criwv_delegate.h"
 #include "ui/base/l10n/l10n_util_mac.h"
 #include "ui/base/resource/resource_bundle.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace ios_web_view {
 
 CRIWVWebMainParts::CRIWVWebMainParts(id<CRIWVDelegate> delegate) {
   delegate_ = delegate;
 }
 
 CRIWVWebMainParts::~CRIWVWebMainParts() {}
 
 void CRIWVWebMainParts::PreMainMessageLoopRun() {
   // Initialize resources.
@@ skipping 13 matching lines @@
   translate::TranslateDownloadManager* download_manager =
       translate::TranslateDownloadManager::GetInstance();
   // TODO(crbug.com/679895): See if we need the system request context here.
   download_manager->set_request_context(browser_state_->GetRequestContext());
   // TODO(crbug.com/679895): Bring up application locale correctly.
   download_manager->set_application_locale(l10n_util::GetLocaleOverride());
   download_manager->language_list()->SetResourceRequestsAllowed(true);
 }
 
 }  // namespace ios_web_view