Replace scoped_ptr with unique_ptr in webrtc/base/

webrtc/api/webrtcsession.cc

Index: webrtc/api/webrtcsession.cc
diff --git a/webrtc/api/webrtcsession.cc b/webrtc/api/webrtcsession.cc
index f51d4cd479348a8bbc10c688220376fb3cd31bc4..28d2f63ef7ace44f618b2e79840f7d34fb4bbe93 100644
--- a/webrtc/api/webrtcsession.cc
+++ b/webrtc/api/webrtcsession.cc
@@ -1039,7 +1039,7 @@ bool WebRtcSession::GetLocalCertificate(
                                                     certificate);
 }
 
-rtc::scoped_ptr<rtc::SSLCertificate> WebRtcSession::GetRemoteSSLCertificate(
+std::unique_ptr<rtc::SSLCertificate> WebRtcSession::GetRemoteSSLCertificate(
     const std::string& transport_name) {
   ASSERT(signaling_thread()->IsCurrent());
   return transport_controller_->GetRemoteSSLCertificate(transport_name);