Cast: Let the extension control if DSCP is on or off.

chrome/browser/media/cast_transport_host_filter.cc

Index: chrome/browser/media/cast_transport_host_filter.cc
diff --git a/chrome/browser/media/cast_transport_host_filter.cc b/chrome/browser/media/cast_transport_host_filter.cc
index d2974370aa0940ad1f5cd26eb28ab5364ac4ffb4..a7bf053f110501a1675162b34d50cd4d1c964490 100644
--- a/chrome/browser/media/cast_transport_host_filter.cc
+++ b/chrome/browser/media/cast_transport_host_filter.cc
@@ -82,7 +82,8 @@ void CastTransportHostFilter::SendCastMessage(
 
 void CastTransportHostFilter::OnNew(
     int32 channel_id,
-    const net::IPEndPoint& remote_end_point) {
+    const net::IPEndPoint& remote_end_point,
+    const std::string& options) {
   if (!power_save_blocker_) {
     DVLOG(1) << ("Preventing the application from being suspended while one or "
                  "more transports are active for Cast Streaming.");
@@ -100,6 +101,7 @@ void CastTransportHostFilter::OnNew(
           g_browser_process->net_log(),
           &clock_,
           remote_end_point,
+          options,
           base::Bind(&CastTransportHostFilter::NotifyStatusChange,
                      weak_factory_.GetWeakPtr(),
                      channel_id),