Add Cast PLI support on sender side.

chrome/renderer/media/cast_transport_sender_ipc.cc

Index: chrome/renderer/media/cast_transport_sender_ipc.cc
diff --git a/chrome/renderer/media/cast_transport_sender_ipc.cc b/chrome/renderer/media/cast_transport_sender_ipc.cc
index 03f3ca8d8d35721ea95e792fdf0a1c4bfcd0cf8e..c723240d5df56ac12ab02584c384d59e86a733cf 100644
--- a/chrome/renderer/media/cast_transport_sender_ipc.cc
+++ b/chrome/renderer/media/cast_transport_sender_ipc.cc
@@ -47,18 +47,22 @@ CastTransportSenderIPC::~CastTransportSenderIPC() {
 void CastTransportSenderIPC::InitializeAudio(
     const media::cast::CastTransportRtpConfig& config,
     const media::cast::RtcpCastMessageCallback& cast_message_cb,
-    const media::cast::RtcpRttCallback& rtt_cb) {
+    const media::cast::RtcpRttCallback& rtt_cb,
+    const media::cast::RtcpPliCallback& pli_cb) {
   clients_[config.ssrc].cast_message_cb = cast_message_cb;
   clients_[config.ssrc].rtt_cb = rtt_cb;
+  clients_[config.ssrc].pli_cb = pli_cb;
   Send(new CastHostMsg_InitializeAudio(channel_id_, config));
 }
 
 void CastTransportSenderIPC::InitializeVideo(
     const media::cast::CastTransportRtpConfig& config,
     const media::cast::RtcpCastMessageCallback& cast_message_cb,
-    const media::cast::RtcpRttCallback& rtt_cb) {
+    const media::cast::RtcpRttCallback& rtt_cb,
+    const media::cast::RtcpPliCallback& pli_cb) {
   clients_[config.ssrc].cast_message_cb = cast_message_cb;
   clients_[config.ssrc].rtt_cb = rtt_cb;
+  clients_[config.ssrc].pli_cb = pli_cb;
   Send(new CastHostMsg_InitializeVideo(channel_id_, config));
 }
 
@@ -102,6 +106,7 @@ void CastTransportSenderIPC::SendRtcpFromRtpReceiver(
     uint32_t sender_ssrc,
     const media::cast::RtcpTimeData& time_data,
     const media::cast::RtcpCastMessage* cast_message,
+    const media::cast::RtcpPliMessage* pli_message,
     base::TimeDelta target_delay,
     const media::cast::ReceiverRtcpEventSubscriber::RtcpEvents* rtcp_events,
     const media::cast::RtpReceiverStatistics* rtp_receiver_statistics) {
@@ -116,6 +121,10 @@ void CastTransportSenderIPC::SendRtcpFromRtpReceiver(
     params.cast_message.reset(
         const_cast<media::cast::RtcpCastMessage*>(cast_message));
   }
+  if (pli_message) {
+    params.pli_message.reset(

[dcheng, 2016/03/01 23:44:12]

Maybe the parameters shouldn't be const?

[xjz, 2016/03/02 04:24:17]

The const_cast is used here only for the purpose to set the scoped ptrs in
|params|. The content will not be modified. 

[dcheng, 2016/03/02 07:41:24]

But what's the point of making it const? Either the scoped_ptr<> itself should
contain a const pointer (rare) or the parameters should just be non-const.
const_cast<> is usually a sign to the reader that they have to pay more
attention because something tricky is happening. Using it like this just adds
noise to the signal.

[xjz, 2016/03/16 00:25:50]

Not applicable.

+        const_cast<media::cast::RtcpPliMessage*>(pli_message));
+  }
   params.target_delay = target_delay;
   if (rtcp_events) {
     params.rtcp_events.reset(
@@ -134,6 +143,7 @@ void CastTransportSenderIPC::SendRtcpFromRtpReceiver(
 
   ignore_result(params.rtp_receiver_statistics.release());
   ignore_result(params.cast_message.release());
+  ignore_result(params.pli_message.release());
   ignore_result(params.rtcp_events.release());
 }
 
@@ -184,6 +194,17 @@ void CastTransportSenderIPC::OnRtcpCastMessage(
   it->second.cast_message_cb.Run(cast_message);
 }
 
+void CastTransportSenderIPC::OnReceivedPli(uint32_t ssrc) {
+  ClientMap::iterator it = clients_.find(ssrc);
+  if (it == clients_.end()) {
+    LOG(ERROR) << "Received picture loss indicator from for unknown SSRC: "
+               << ssrc;
+    return;
+  }
+  if (!it->second.pli_cb.is_null())
+    it->second.pli_cb.Run();
+}
+
 void CastTransportSenderIPC::OnReceivedPacket(
     const media::cast::Packet& packet) {
   if (!packet_callback_.is_null()) {