MD Settings: Convert C++ handlers to be JavaScript-lifecycle aware.

chrome/browser/ui/webui/settings/languages_handler.h

 // Copyright (c) 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_SETTINGS_LANGUAGES_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_SETTINGS_LANGUAGES_HANDLER_H_
 
 #include "base/macros.h"
 #include "chrome/browser/ui/webui/settings/settings_page_ui_handler.h"
 
@@ skipping 10 matching lines @@
 namespace settings {
 
 // Chrome "Languages" settings page UI handler.
 class LanguagesHandler : public SettingsPageUIHandler {
  public:
   explicit LanguagesHandler(content::WebUI* webui);
   ~LanguagesHandler() override;
 
   // SettingsPageUIHandler implementation.
   void RegisterMessages() override;
+  void OnJavascriptAllowed() override {}
+  void OnJavascriptDisallowed() override {}
 
  private:
   // Changes the UI language, provided the user is allowed to do so.
   void HandleSetUILanguage(const base::ListValue* args);
 
   // Restarts Chrome to apply a UI language change.
   void HandleRestart(const base::ListValue* args);
 
   Profile* profile_;  // Weak pointer.
 
   DISALLOW_COPY_AND_ASSIGN(LanguagesHandler);
 };
 
 }  // namespace settings
 
 #endif  // CHROME_BROWSER_UI_WEBUI_SETTINGS_LANGUAGES_HANDLER_H_