Reland of move remote tree host and some related input and metro_driver code

chrome/browser/browser_process_platform_part_aurawin.h

-// Copyright (c) 2013 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_BROWSER_PROCESS_PLATFORM_PART_AURAWIN_H_
-#define CHROME_BROWSER_BROWSER_PROCESS_PLATFORM_PART_AURAWIN_H_
-
-#include "base/compiler_specific.h"
-#include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
-#include "chrome/browser/browser_process_platform_part_base.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
-
-class ChromeMetroViewerProcessHost;
-
-class BrowserProcessPlatformPart : public BrowserProcessPlatformPartBase,
-                                   public content::NotificationObserver {
- public:
-  BrowserProcessPlatformPart();
-  ~BrowserProcessPlatformPart() override;
-
-  // Invoked when the ASH metro viewer process on Windows 8 exits.
-  void OnMetroViewerProcessTerminated();
-
-  // Overridden from BrowserProcessPlatformPartBase:
-  void PlatformSpecificCommandLineProcessing(
-      const base::CommandLine& command_line) override;
-
-  // content::NotificationObserver method:
-  void Observe(int type,
-               const content::NotificationSource& source,
-               const content::NotificationDetails& details) override;
-
- private:
-  // Hosts the channel for the Windows 8 metro viewer process which runs in
-  // the ASH environment.
-  scoped_ptr<ChromeMetroViewerProcessHost> metro_viewer_process_host_;
-
-  content::NotificationRegistrar registrar_;
-
-  DISALLOW_COPY_AND_ASSIGN(BrowserProcessPlatformPart);
-};
-
-#endif  // CHROME_BROWSER_BROWSER_PROCESS_PLATFORM_PART_AURAWIN_H_