[Cast] Clean-up RtpCastHeader and RtpParser, removing the last WebRTC dependency.

media/cast/framer/frame_buffer.cc

 // Copyright 2013 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.
 
 #include "media/cast/framer/frame_buffer.h"
 
 #include "base/logging.h"
 
 namespace media {
 namespace cast {
@@ skipping 10 matching lines @@
 FrameBuffer::~FrameBuffer() {}
 
 void FrameBuffer::InsertPacket(const uint8* payload_data,
                                size_t payload_size,
                                const RtpCastHeader& rtp_header) {
   // Is this the first packet in the frame?
   if (packets_.empty()) {
     frame_id_ = rtp_header.frame_id;
     max_packet_id_ = rtp_header.max_packet_id;
     is_key_frame_ = rtp_header.is_key_frame;
-    if (rtp_header.is_reference) {
-      last_referenced_frame_id_ = rtp_header.reference_frame_id;
-    } else {
-      last_referenced_frame_id_ = rtp_header.frame_id - 1;
-    }
-
-    rtp_timestamp_ = rtp_header.webrtc.header.timestamp;
+    last_referenced_frame_id_ = rtp_header.reference_frame_id;
+    rtp_timestamp_ = rtp_header.rtp_timestamp;
   }
   // Is this the correct frame?
   if (rtp_header.frame_id != frame_id_)
     return;
 
   // Insert every packet only once.
   if (packets_.find(rtp_header.packet_id) != packets_.end()) {
     return;
   }
 
@@ skipping 50 matching lines @@
   PacketMap::const_iterator it;
   for (it = packets_.begin(); it != packets_.end(); ++it) {
     video_frame->data.insert(
         video_frame->data.end(), it->second.begin(), it->second.end());
   }
   return true;
 }
 
 }  // namespace cast
 }  // namespace media