Convert //media/blink from scoped_ptr to std::unique_ptr

media/blink/websourcebuffer_impl.cc

Index: media/blink/websourcebuffer_impl.cc
diff --git a/media/blink/websourcebuffer_impl.cc b/media/blink/websourcebuffer_impl.cc
index e4aa84df39ef90a7e56540b1ff5e47a404105d10..5482406070fdd66695cb7ecd1867585d141b76fd 100644
--- a/media/blink/websourcebuffer_impl.cc
+++ b/media/blink/websourcebuffer_impl.cc
@@ -173,7 +173,8 @@ blink::WebMediaPlayer::TrackType mediaTrackTypeToBlink(MediaTrack::Type type) {
   return blink::WebMediaPlayer::AudioTrack;
 }
 
-void WebSourceBufferImpl::InitSegmentReceived(scoped_ptr<MediaTracks> tracks) {
+void WebSourceBufferImpl::InitSegmentReceived(
+    std::unique_ptr<MediaTracks> tracks) {
   DCHECK(tracks.get());
   DVLOG(1) << __FUNCTION__ << " tracks=" << tracks->tracks().size();