[Mojo Video Capture] Replace const scoped_refptr<T>& with scoped_refptr<T> and use std::move

media/capture/video/video_frame_receiver.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.
 
 #include "media/capture/capture_export.h"
 #include "media/capture/video/video_capture_device.h"
 
 namespace media {
 
 // Callback interface for VideoCaptureDeviceClient to communicate with its
 // clients.
 class CAPTURE_EXPORT VideoFrameReceiver {
  public:
   virtual ~VideoFrameReceiver(){};
 
   virtual void OnIncomingCapturedVideoFrame(
       std::unique_ptr<media::VideoCaptureDevice::Client::Buffer> buffer,
-      const scoped_refptr<media::VideoFrame>& frame) = 0;
+      scoped_refptr<media::VideoFrame> frame) = 0;
   virtual void OnError() = 0;
   virtual void OnLog(const std::string& message) = 0;
   virtual void OnBufferDestroyed(int buffer_id_to_drop) = 0;
 };
 
 }  // namespace media