Reland: Add support for $i18n{} localized strings to ios/web.

ios/chrome/browser/ui/webui/flags_ui.cc

 // Copyright 2015 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/webui/flags_ui.h"
 
 #include <string>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 37 matching lines @@
         IDS_FLAGS_UI_ALTERNATIVES_UI_NO_EXPERIMENTS_AVAILABLE);
   } else {
     source->AddLocalizedString(flags_ui::kFlagsLongTitle,
                                IDS_FLAGS_UI_LONG_TITLE);
     source->AddLocalizedString(flags_ui::kFlagsTableTitle,
                                IDS_FLAGS_UI_TABLE_TITLE);
   }
   source->AddLocalizedString(flags_ui::kFlagsWarningHeader,
                              IDS_FLAGS_UI_WARNING_HEADER);
   source->AddLocalizedString(flags_ui::kFlagsBlurb, IDS_FLAGS_UI_WARNING_TEXT);
+  source->AddLocalizedString(flags_ui::kChannelPromoBeta,
+                             IDS_FLAGS_UI_PROMOTE_BETA_CHANNEL);
+  source->AddLocalizedString(flags_ui::kChannelPromoDev,
+                             IDS_FLAGS_UI_PROMOTE_DEV_CHANNEL);
   source->AddLocalizedString(flags_ui::kFlagsUnsupportedTableTitle,
                              IDS_FLAGS_UI_UNSUPPORTED_TABLE_TITLE);
   source->AddLocalizedString(flags_ui::kFlagsNotSupported,
                              IDS_FLAGS_UI_NOT_AVAILABLE);
   source->AddLocalizedString(flags_ui::kFlagsRestartNotice,
                              IDS_FLAGS_UI_RELAUNCH_NOTICE);
   source->AddLocalizedString(flags_ui::kFlagsRestartButton,
                              IDS_FLAGS_UI_RELAUNCH_BUTTON);
   source->AddLocalizedString(flags_ui::kResetAllButton,
                              IDS_FLAGS_UI_RESET_ALL_BUTTON);
@@ skipping 176 matching lines @@
 ///////////////////////////////////////////////////////////////////////////////
 //
 // AppleFlagsUI
 //
 ///////////////////////////////////////////////////////////////////////////////
 
 AppleFlagsUI::AppleFlagsUI(web::WebUIIOS* web_ui)
     : BaseFlagsUI(web_ui, BaseFlagsUI::FLAGS_UI_APPLE) {}
 
 AppleFlagsUI::~AppleFlagsUI() {}