message: setCodecPreferences: dont insert red codec twice
  this could happen if setCodecPreferences is used to prefer
  red over opus as it is done for red+opus.
  Cr-Commit-Position: refs/heads/main@{#35344}
diff: @@ -1084,6 +1084,9 @@ static Codecs MatchCodecPreference(
  break;
  }
  } else if (IsRedCodec(codec)) {
  + // For RED, do not insert the codec again if it was already
  + // inserted. audio/red for opus gets enabled by having RED before
  + // the primary codec.
  const auto fmtp =
  codec.params.find(cricket::kCodecParamNotInNameValueFormat);
  if (fmtp != codec.params.end()) {
  @@ -1091,7 +1094,10 @@ static Codecs MatchCodecPreference(
  rtc::split(fmtp->second, '/', &redundant_payloads);
  if (redundant_payloads.size() > 0 &&
  redundant_payloads[0] == id) {
  + if (std::find(filtered_codecs.begin(), filtered_codecs.end(),
  + codec) == filtered_codecs.end()) {
  filtered_codecs.push_back(codec);
  + }
  break;
  }
  }
  