Initialize ios/web_view translate with a system-wide URLRequestContext.

ios/web_view/internal/translate/web_view_translate_service.cc

+// Copyright 2017 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/web_view/internal/translate/web_view_translate_service.h"
+
+#include "base/memory/singleton.h"
+#include "components/translate/core/browser/translate_download_manager.h"
+#include "ios/web_view/internal/app/application_context.h"
+
+namespace ios_web_view {
+
+WebViewTranslateService::TranslateRequestsAllowedListener::
+    TranslateRequestsAllowedListener()
+    : resource_request_allowed_notifier_(
+          ios_web_view::ApplicationContext::GetInstance()->GetLocalState(),
+          nullptr) {

[Eugene But (OOO till 7-30), 2017/05/31 16:25:34]

nit: /*name_of_the_argument=*/nullptr

[michaeldo, 2017/05/31 21:03:43]

Done.

+  resource_request_allowed_notifier_.Init(this);
+}
+
+WebViewTranslateService::TranslateRequestsAllowedListener::
+    ~TranslateRequestsAllowedListener(){};

[sdefresne, 2017/05/31 08:52:46]

Remove trailing semi-colon.

[michaeldo, 2017/05/31 21:03:43]

Done.

+
+void WebViewTranslateService::TranslateRequestsAllowedListener::
+    OnResourceRequestsAllowed() {
+  translate::TranslateLanguageList* language_list =
+      translate::TranslateDownloadManager::GetInstance()->language_list();
+  if (!language_list) {
+    NOTREACHED();

[Eugene But (OOO till 7-30), 2017/05/31 16:25:34]

This should be either NOTREACHED or early return, not both:
https://chromium.googlesource.com/chromium/src/+/master/styleguide/c++/c++.md...

[michaeldo, 2017/05/31 21:03:43]

Done.

+    return;
+  }
+
+  language_list->SetResourceRequestsAllowed(
+      resource_request_allowed_notifier_.ResourceRequestsAllowed());
+}
+
+WebViewTranslateService* WebViewTranslateService::GetInstance() {
+  return base::Singleton<WebViewTranslateService>::get();
+}
+
+WebViewTranslateService::WebViewTranslateService()
+    : translate_requests_allowed_listener_(
+          new TranslateRequestsAllowedListener()){};

[sdefresne, 2017/05/31 08:52:46]

Use "base::MakeUnique<>" here.

Remove trailing semi-colon.

[michaeldo, 2017/05/31 21:03:43]

Done.

+
+WebViewTranslateService::~WebViewTranslateService() = default;
+
+void WebViewTranslateService::Initialize() {
+  // Initialize the allowed state for resource requests.
+  translate_requests_allowed_listener_->OnResourceRequestsAllowed();
+
+  // Initialize translate.
+  translate::TranslateDownloadManager* download_manager =
+      translate::TranslateDownloadManager::GetInstance();
+  download_manager->set_request_context(
+      ios_web_view::ApplicationContext::GetInstance()
+          ->GetSystemURLRequestContext());
+  download_manager->set_application_locale(
+      ios_web_view::ApplicationContext::GetInstance()->GetApplicationLocale());
+}
+
+void WebViewTranslateService::Shutdown() {
+  translate::TranslateDownloadManager* download_manager =
+      translate::TranslateDownloadManager::GetInstance();
+  download_manager->Shutdown();
+}
+
+}  // namespace ios_web_view