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

webrtc/media/engine/webrtcvideocapturerfactory.h

Index: webrtc/media/engine/webrtcvideocapturerfactory.h
diff --git a/webrtc/media/engine/webrtcvideocapturerfactory.h b/webrtc/media/engine/webrtcvideocapturerfactory.h
index 128ef9d80de28f680b0a8b04afaf7715b3564c3c..c1f91b70f6126eec412ee65ec6f481e5c796b60b 100644
--- a/webrtc/media/engine/webrtcvideocapturerfactory.h
+++ b/webrtc/media/engine/webrtcvideocapturerfactory.h
@@ -19,7 +19,7 @@ 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