Cleanup Tool WebUI: Add HTML content and styling with dummy JS

chrome/browser/ui/webui/cleanup_tool/cleanup_tool_ui.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_CLEANUP_TOOL_CLEANUP_TOOL_UI_H_
 #define CHROME_BROWSER_UI_WEBUI_CLEANUP_TOOL_CLEANUP_TOOL_UI_H_
 
 #include "base/macros.h"
 #include "content/public/browser/web_ui_controller.h"
 
 // The UI for chrome://cleanup, which will allow Windows users to see the
 // status of the last Chrome Cleanup Tool scan and to manually launch the
 // cleanup process.
 class CleanupToolUI : public content::WebUIController {
  public:
   explicit CleanupToolUI(content::WebUI* web_ui);
+  ~CleanupToolUI() override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(CleanupToolUI);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_CLEANUP_TOOL_CLEANUP_TOOL_UI_H_