Refactor: simplify interface of SenderRtcpSession and CastTransport.

media/cast/net/rtcp/rtcp_defines.h

Index: media/cast/net/rtcp/rtcp_defines.h
diff --git a/media/cast/net/rtcp/rtcp_defines.h b/media/cast/net/rtcp/rtcp_defines.h
index 3455d4f5360491e6c687e0f91d9f5a85d0c20b98..fba8692153b7e5ef86c0662390fac98497becbb8 100644
--- a/media/cast/net/rtcp/rtcp_defines.h
+++ b/media/cast/net/rtcp/rtcp_defines.h
@@ -126,12 +126,6 @@ struct RtcpEvent {
   uint16_t packet_id;
 };
 
-typedef base::Callback<void(const RtcpCastMessage&)> RtcpCastMessageCallback;
-typedef base::Callback<void(base::TimeDelta)> RtcpRttCallback;
-typedef
-base::Callback<void(const RtcpReceiverLogMessage&)> RtcpLogMessageCallback;
-typedef base::Callback<void()> RtcpPliCallback;
-
 // TODO(hubbe): Document members of this struct.
 struct RtpReceiverStatistics {
   RtpReceiverStatistics();
@@ -156,11 +150,11 @@ struct SendRtcpFromRtpReceiver_Params {
   uint32_t ssrc;
   uint32_t sender_ssrc;
   RtcpTimeData time_data;
-  scoped_ptr<RtcpCastMessage> cast_message;
-  scoped_ptr<RtcpPliMessage> pli_message;
+  std::unique_ptr<RtcpCastMessage> cast_message;
+  std::unique_ptr<RtcpPliMessage> pli_message;
   base::TimeDelta target_delay;
-  scoped_ptr<std::vector<std::pair<RtpTimeTicks, RtcpEvent>>> rtcp_events;
-  scoped_ptr<RtpReceiverStatistics> rtp_receiver_statistics;
+  std::unique_ptr<std::vector<std::pair<RtpTimeTicks, RtcpEvent>>> rtcp_events;
+  std::unique_ptr<RtpReceiverStatistics> rtp_receiver_statistics;
 };