Make RTX pt/apt reconfigurable by calling WebRtcVideoChannel2::SetRecvParameters.

webrtc/call/rampup_tests.cc

Index: webrtc/call/rampup_tests.cc
diff --git a/webrtc/call/rampup_tests.cc b/webrtc/call/rampup_tests.cc
index f637f7757735e628d137956ba13cd31100769176..d8f0592ec42d1ca489b9eb6afacd3c495e30b3bf 100644
--- a/webrtc/call/rampup_tests.cc
+++ b/webrtc/call/rampup_tests.cc
@@ -199,10 +199,10 @@ void RampUpTester::ModifyVideoConfigs(
     }
 
     if (rtx_) {
-      recv_config.rtp.rtx[send_config->encoder_settings.payload_type].ssrc =
-          video_rtx_ssrcs_[i];
-      recv_config.rtp.rtx[send_config->encoder_settings.payload_type]
-          .payload_type = send_config->rtp.rtx.payload_type;
+      recv_config.rtp.rtx_ssrc = video_rtx_ssrcs_[i];
+      recv_config.rtp
+          .rtx_payload_types[send_config->encoder_settings.payload_type] =
+          send_config->rtp.rtx.payload_type;
     }
     ++i;
   }