Set the preferred DSCP value for Rtp data channel to be DSCP_AF41.

webrtc/media/sctp/sctpdataengine_unittest.cc

 /*
  *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 247 matching lines @@
     StreamParams p(StreamParams::CreateLegacy(ssrc));
     ret = ret && chan1_->AddSendStream(p);
     ret = ret && chan1_->AddRecvStream(p);
     ret = ret && chan2_->AddSendStream(p);
     ret = ret && chan2_->AddRecvStream(p);
     return ret;
   }
 
   SctpDataMediaChannel* CreateChannel(SctpFakeNetworkInterface* net,
                                       SctpFakeDataReceiver* recv) {
-    SctpDataMediaChannel* channel =
-        static_cast<SctpDataMediaChannel*>(engine_->CreateChannel(DCT_SCTP));
+    cricket::MediaConfig config;
+    SctpDataMediaChannel* channel = static_cast<SctpDataMediaChannel*>(
+        engine_->CreateChannel(DCT_SCTP, config));
     channel->SetInterface(net);
     // When data is received, pass it to the SctpFakeDataReceiver.
     channel->SignalDataReceived.connect(
         recv, &SctpFakeDataReceiver::OnDataReceived);
     return channel;
   }
 
   bool SendData(SctpDataMediaChannel* chan,
                 uint32_t ssrc,
                 const std::string& msg,
@@ skipping 233 matching lines @@
   // Create a new channel 1.
   AddStream(1);
   ASSERT_TRUE(SendData(channel1(), 1, "hi?", &result));
   EXPECT_EQ(SDR_SUCCESS, result);
   EXPECT_TRUE_WAIT(ReceivedData(receiver2(), 1, "hi?"), 1000);
   channel1()->RemoveSendStream(1);
   EXPECT_TRUE_WAIT(chan_2_sig_receiver.StreamCloseCount(1) == 2, 1000);
 }
 
 }  // namespace cricket