Explicitly only add transport-cc RTCP feedback param to default FlexFEC codec.

webrtc/media/engine/internalencoderfactory.cc

Index: webrtc/media/engine/internalencoderfactory.cc
diff --git a/webrtc/media/engine/internalencoderfactory.cc b/webrtc/media/engine/internalencoderfactory.cc
index ec9837579ba8a01a8e384d41aa858550b81c1cb2..ad3a4be0c6d03ce4e06bf331a9596aedb6c30aae 100644
--- a/webrtc/media/engine/internalencoderfactory.cc
+++ b/webrtc/media/engine/internalencoderfactory.cc
@@ -53,6 +53,10 @@ InternalEncoderFactory::InternalEncoderFactory() {
     // we never use the actual value anywhere in our code however.
     // TODO(brandtr): Consider honouring this value in the sender and receiver.
     flexfec_codec.SetParam(kFlexfecFmtpRepairWindow, "10000000");
+    flexfec_codec.AddFeedbackParam(
+        FeedbackParam(kRtcpFbParamTransportCc, kParamValueEmpty));
+    flexfec_codec.AddFeedbackParam(
+        FeedbackParam(kRtcpFbParamRemb, kParamValueEmpty));
     supported_codecs_.push_back(flexfec_codec);
   }
 }