Cast: Avoid retransmit if we sent the same packet recently (less than RTT)

chrome/common/cast_messages.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.
 
 // IPC messages for the Cast transport API.
 // Multiply-included message file, hence no include guard.
 
 #include "ipc/ipc_message_macros.h"
 #include "media/cast/cast_sender.h"
 #include "media/cast/logging/logging_defines.h"
@@ skipping 115 matching lines @@
     CastHostMsg_InsertCodedVideoFrame,
     int32 /* channel_id */,
     media::cast::transport::EncodedFrame /* video_frame */)
 
 IPC_MESSAGE_CONTROL3(
     CastHostMsg_SendRtcpFromRtpSender,
     int32 /* channel_id */,
     media::cast::transport::SendRtcpFromRtpSenderData /* data */,
     media::cast::transport::RtcpDlrrReportBlock /* dlrr */)
 
-IPC_MESSAGE_CONTROL4(
+IPC_MESSAGE_CONTROL5(
     CastHostMsg_ResendPackets,
     int32 /* channel_id */,
     bool /* is_audio */,
     media::cast::MissingFramesAndPacketsMap /* missing_packets */,
-    bool /* cancel_rtx_if_not_in_list */)
+    bool /* cancel_rtx_if_not_in_list */,
+    base::TimeDelta /* dedupe_window */)
 
 IPC_MESSAGE_CONTROL2(
     CastHostMsg_New,
     int32 /* channel_id */,
     net::IPEndPoint /*remote_end_point*/);
 
 IPC_MESSAGE_CONTROL1(
     CastHostMsg_Delete,
     int32 /* channel_id */);