cast: Split Rtcp into two for sender and receiver

media/cast/net/rtcp/rtcp_utility.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef MEDIA_CAST_RTCP_RTCP_UTILITY_H_
-#define MEDIA_CAST_RTCP_RTCP_UTILITY_H_
+#ifndef MEDIA_CAST_NET_RTCP_RTCP_UTILITY_H_
+#define MEDIA_CAST_NET_RTCP_RTCP_UTILITY_H_
 
 #include "base/big_endian.h"
 #include "media/cast/logging/logging_defines.h"
 #include "media/cast/net/cast_transport_config.h"
 #include "media/cast/net/rtcp/rtcp_defines.h"
 
 namespace media {
 namespace cast {
 
 // RFC 3550 page 44, including end null.
@@ skipping 111 matching lines @@
 // Maps a base::TimeTicks value to an NTP timestamp comprised of two components.
 void ConvertTimeTicksToNtp(const base::TimeTicks& time,
                            uint32_t* ntp_seconds,
                            uint32_t* ntp_fractions);
 
 // Maps an NTP timestamp, comprised of two components, to a base::TimeTicks
 // value.
 base::TimeTicks ConvertNtpToTimeTicks(uint32_t ntp_seconds,
                                       uint32_t ntp_fractions);
 
+bool IsRtcpPacket(const uint8_t* packet, size_t length);
+
+uint32_t GetSsrcOfSender(const uint8_t* rtcp_buffer, size_t length);
+
 }  // namespace cast
 }  // namespace media
 
-#endif  // MEDIA_CAST_RTCP_RTCP_UTILITY_H_
+#endif  // MEDIA_CAST_NET_RTCP_RTCP_UTILITY_H_