message: Avoid triggering a false error logging when using encryptor and sending DTX.
  Cr-Commit-Position: refs/heads/master@{#28351}
diff: @@ -516,7 +516,8 @@ int32_t ChannelSend::SendRtpAudio(AudioFrameType frameType,
  // DTMF, or the encoder entered DTX.
  // TODO(minyue): see whether DTMF packets should be encrypted or not. In
  // current implementation, they are not.
  - if (frame_encryptor_ != nullptr && !payload.empty()) {
  + if (!payload.empty()) {
  + if (frame_encryptor_ != nullptr) {
  // TODO(benwright@webrtc.org) - Allocate enough to always encrypt inline.
  // Allocate a buffer to hold the maximum possible encrypted payload.
  size_t max_ciphertext_size = frame_encryptor_->GetMaxCiphertextByteSize(
  @@ -530,7 +531,8 @@ int32_t ChannelSend::SendRtpAudio(AudioFrameType frameType,
  /*additional_data=*/nullptr, payload, encrypted_audio_payload,
  &bytes_written);
  if (encrypt_status != 0) {
  - RTC_DLOG(LS_ERROR) << "Channel::SendData() failed encrypt audio payload: "
  + RTC_DLOG(LS_ERROR)
  + << "Channel::SendData() failed encrypt audio payload: "
  << encrypt_status;
  return -1;
  }
  @@ -543,6 +545,7 @@ int32_t ChannelSend::SendRtpAudio(AudioFrameType frameType,
  << "A frame encryptor is required but one is not set.";
  return -1;
  }
  + }
  // Push data from ACM to RTP/RTCP-module to deliver audio frame for
  // packetization.
  