Cast: Use DSCP AF41 for all traffic if possible.

media/cast/transport/cast_transport_sender_impl.cc

 // 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.
 
 #include "media/cast/transport/cast_transport_sender_impl.h"
 
 #include "base/single_thread_task_runner.h"
 #include "media/cast/transport/cast_transport_config.h"
 #include "media/cast/transport/cast_transport_defines.h"
+#include "net/base/net_util.h"
 
 namespace media {
 namespace cast {
 namespace transport {
 
 scoped_ptr<CastTransportSender> CastTransportSender::Create(
     net::NetLog* net_log,
     base::TickClock* clock,
     const net::IPEndPoint& remote_end_point,
     const CastTransportStatusCallback& status_callback,
@@ skipping 39 matching lines @@
   DCHECK(clock_);
   if (!raw_events_callback_.is_null()) {
     DCHECK(raw_events_callback_interval > base::TimeDelta());
     event_subscriber_.reset(new SimpleEventSubscriber);
     logging_.AddRawEventSubscriber(event_subscriber_.get());
     raw_events_timer_.Start(FROM_HERE,
                             raw_events_callback_interval,
                             this,
                             &CastTransportSenderImpl::SendRawEvents);
   }
+  if (transport_) {
+    // The default DSCP value for cast is AF41. Which gives it a higher
+    // priority over other traffic.
+    transport_->SetDscp(net::DSCP_AF41);
+  }
 }
 
 CastTransportSenderImpl::~CastTransportSenderImpl() {
   if (event_subscriber_.get())
     logging_.RemoveRawEventSubscriber(event_subscriber_.get());
 }
 
 void CastTransportSenderImpl::InitializeAudio(
     const CastTransportAudioConfig& config) {
   LOG_IF(WARNING, config.rtp.config.aes_key.empty() ||
@@ skipping 115 matching lines @@
   DCHECK(event_subscriber_.get());
   DCHECK(!raw_events_callback_.is_null());
   std::vector<PacketEvent> packet_events;
   event_subscriber_->GetPacketEventsAndReset(&packet_events);
   raw_events_callback_.Run(packet_events);
 }
 
 }  // namespace transport
 }  // namespace cast
 }  // namespace media