cast: Split Rtcp into two for sender and receiver

media/cast/net/rtcp/rtcp_session.h

Index: media/cast/net/rtcp/rtcp_session.h
diff --git a/media/cast/net/rtcp/rtcp_session.h b/media/cast/net/rtcp/rtcp_session.h
new file mode 100644
index 0000000000000000000000000000000000000000..6020342fa72f4842af45e536bebb8c882de7b9cf
--- /dev/null
+++ b/media/cast/net/rtcp/rtcp_session.h
@@ -0,0 +1,25 @@
+// Copyright (c) 2015 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_NET_RTCP_RTCP_SESSION_H_
+#define MEDIA_CAST_NET_RTCP_RTCP_SESSION_H_
+
+namespace media {
+namespace cast {
+
+// Base class for an RTCP session.
+class RtcpSession {
+ public:
+  virtual ~RtcpSession() {}
+
+  // Handle incoming RTCP packet.
+  // Returns false if it is not a RTCP packet or it is not directed to
+  // this session, e.g. SSRC doesn't match.
+  virtual bool IncomingRtcpPacket(const uint8* data, size_t length) = 0;
+};
+
+}  // namespace cast
+}  // namespace media
+
+#endif  // MEDIA_CAST_NET_RTCP_RTCP_SESSION_H_