[Mojo Video Capture] Implement a VideoCaptureProvider using the Mojo service (part 1)

content/browser/renderer_host/media/in_process_video_capture_provider.h

 // Copyright 2016 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 CONTENT_BROWSER_RENDERER_HOST_MEDIA_IN_PROCESS_VIDEO_CAPTURE_SYSTEM_H_
 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_IN_PROCESS_VIDEO_CAPTURE_SYSTEM_H_
 
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
 #include "content/browser/renderer_host/media/video_capture_provider.h"
 #include "media/capture/video/video_capture_system.h"
 
 namespace content {
 
 class CONTENT_EXPORT InProcessVideoCaptureProvider
     : public VideoCaptureProvider {
  public:
   InProcessVideoCaptureProvider(
       std::unique_ptr<media::VideoCaptureSystem> video_capture_system,
       scoped_refptr<base::SingleThreadTaskRunner> device_task_runner);
   ~InProcessVideoCaptureProvider() override;
 
+  void Uninitialize() override;
+
   void GetDeviceInfosAsync(
       const base::Callback<void(
           const std::vector<media::VideoCaptureDeviceInfo>&)>& result_callback)
       override;
 
   std::unique_ptr<VideoCaptureDeviceLauncher> CreateDeviceLauncher() override;
 
  private:
   const std::unique_ptr<media::VideoCaptureSystem> video_capture_system_;
   // The message loop of media stream device thread, where VCD's live.
   scoped_refptr<base::SingleThreadTaskRunner> device_task_runner_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_IN_PROCESS_VIDEO_CAPTURE_SYSTEM_H_