Don't send FEC for H.264 with NACK enabled.

webrtc/video/vie_channel.cc

 /*
  *  Copyright (c) 2012 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 406 matching lines @@
   RTC_DCHECK(sender_);
   for (RtpRtcp* rtp_rtcp : rtp_rtcp_modules_)
     rtp_rtcp->SetRTCPStatus(rtcp_mode);
 }
 
 void ViEChannel::SetProtectionMode(bool enable_nack,
                                    bool enable_fec,
                                    int payload_type_red,
                                    int payload_type_fec) {
   // Validate payload types.
-  if (enable_fec) {
+  if (enable_fec || payload_type_red != -1 || payload_type_fec != -1) {

[stefan-webrtc, 2016/02/12 10:46:27]

Shouldn't this be:
enable_fec && payload_type_red != -1 && payload_type_fec != -1

[pbos-webrtc, 2016/02/12 12:00:27]

Comment updated.

     RTC_DCHECK_GE(payload_type_red, 0);
     RTC_DCHECK_GE(payload_type_fec, 0);
     RTC_DCHECK_LE(payload_type_red, 127);
     RTC_DCHECK_LE(payload_type_fec, 127);
   } else {
+    // Payload types unset.
     RTC_DCHECK_EQ(payload_type_red, -1);
     RTC_DCHECK_EQ(payload_type_fec, -1);
     // Set to valid uint8_ts to be castable later without signed overflows.
     payload_type_red = 0;
     payload_type_fec = 0;
   }
 
   VCMVideoProtection protection_method;
   if (enable_nack) {
     protection_method = enable_fec ? kProtectionNackFEC : kProtectionNack;
@@ skipping 667 matching lines @@
   rtc::CritScope lock(&crit_);
   receive_stats_callback_ = receive_statistics_proxy;
 }
 
 void ViEChannel::SetIncomingVideoStream(
     IncomingVideoStream* incoming_video_stream) {
   rtc::CritScope lock(&crit_);
   incoming_video_stream_ = incoming_video_stream;
 }
 }  // namespace webrtc