Add experiment to disable ulpfec.

webrtc/video/video_send_stream_tests.cc

 /*
  *  Copyright (c) 2013 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.
  */
 #include <algorithm>  // max
@@ skipping 38 matching lines @@
 namespace webrtc {
 
 enum VideoFormat { kGeneric, kVP8, };
 
 void ExpectEqualFramesVector(const std::vector<VideoFrame>& frames1,
                              const std::vector<VideoFrame>& frames2);
 VideoFrame CreateVideoFrame(int width, int height, uint8_t data);
 
 class VideoSendStreamTest : public test::CallTest {
  protected:
+  VideoSendStreamTest() : VideoSendStreamTest(true) {}
+  explicit VideoSendStreamTest(bool enable_ulpfec)
+      : field_trial_(
+            enable_ulpfec ? "" : "WebRTC-DisableUlpFecExperiment/Enabled/") {}
+
   void TestNackRetransmission(uint32_t retransmit_ssrc,
                               uint8_t retransmit_payload_type);
   void TestPacketFragmentationSize(VideoFormat format, bool with_fec);
 
   void TestVp9NonFlexMode(uint8_t num_temporal_layers,
                           uint8_t num_spatial_layers);
 
   void TestRequestSourceRotateVideo(bool support_orientation_ext);
+
+  test::ScopedFieldTrials field_trial_;
 };
 
 TEST_F(VideoSendStreamTest, CanStartStartedStream) {
   task_queue_.SendTask([this]() {
     CreateSenderCall(Call::Config(event_log_.get()));
 
     test::NullTransport transport;
     CreateSendConfig(1, 0, 0, &transport);
     CreateVideoStreams();
     video_send_stream_->Start();
@@ skipping 470 matching lines @@
   UlpfecObserver test(true, false, true, true, "VP8", encoder.get());
   RunBaseTest(&test);
 }
 
 TEST_F(VideoSendStreamTest, SupportsUlpfecWithoutExtensions) {
   std::unique_ptr<VideoEncoder> encoder(VP8Encoder::Create());
   UlpfecObserver test(false, false, true, true, "VP8", encoder.get());
   RunBaseTest(&test);
 }
 
+class VideoSendStreamWithoutUlpfecTest : public VideoSendStreamTest {
+ protected:

[brandtr, 2017/08/23 14:10:44]

Maybe put the ScopedFieldTrials as a member of this class, so you don't have to
make changes to VideoSendStreamTest?

[stefan-webrtc, 2017/08/23 14:27:08]

Yes, I don't know why I did it this way.

+  VideoSendStreamWithoutUlpfecTest() : VideoSendStreamTest(false) {}
+};
+
+TEST_F(VideoSendStreamWithoutUlpfecTest, NoUlpfecIfDisabledThroughFieldTrial) {
+  std::unique_ptr<VideoEncoder> encoder(VP8Encoder::Create());
+  UlpfecObserver test(false, false, true, false, "VP8", encoder.get());
+  RunBaseTest(&test);
+}
+
 // The FEC scheme used is not efficient for H264, so we should not use RED/FEC
 // since we'll still have to re-request FEC packets, effectively wasting
 // bandwidth since the receiver has to wait for FEC retransmissions to determine
 // that the received state is actually decodable.
 TEST_F(VideoSendStreamTest, DoesNotUtilizeUlpfecForH264WithNackEnabled) {
   std::unique_ptr<VideoEncoder> encoder(
       new test::FakeH264Encoder(Clock::GetRealTimeClock()));
   UlpfecObserver test(false, true, true, false, "H264", encoder.get());
   RunBaseTest(&test);
 }
@@ skipping 2923 matching lines @@
       capturer_ = frame_generator_capturer;
     }
 
     test::FrameGeneratorCapturer* capturer_ = nullptr;
   } test;
 
   RunBaseTest(&test);
 }
 
 }  // namespace webrtc