Switching some interfaces to use std::unique_ptr<>.

webrtc/media/engine/webrtcvideocapturerfactory.h

 /*
  *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 // TODO(pthatcher): Rename file to match class name.
 #ifndef WEBRTC_MEDIA_ENGINE_WEBRTCVIDEOCAPTURERFACTORY_H_
 #define WEBRTC_MEDIA_ENGINE_WEBRTCVIDEOCAPTURERFACTORY_H_
 
 #include "webrtc/media/base/videocapturerfactory.h"
 
 namespace cricket {
 
 // Creates instances of cricket::WebRtcVideoCapturer.
 class WebRtcVideoDeviceCapturerFactory : public VideoDeviceCapturerFactory {
  public:
-  virtual VideoCapturer* Create(const Device& device);
+  std::unique_ptr<VideoCapturer> Create(const Device& device) override;
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_MEDIA_ENGINE_WEBRTCVIDEOCAPTURERFACTORY_H_