Experiment-driven configuration of PLR/RPLR-based FecController

webrtc/modules/audio_coding/audio_network_adaptor/fec_controller_plr_based.cc

 /*
  *  Copyright (c) 2016 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 "webrtc/modules/audio_coding/audio_network_adaptor/fec_controller_plr_based.h"
 
 #include <limits>
 #include <utility>
 
 #include "webrtc/base/checks.h"
+#include "webrtc/system_wrappers/include/field_trial.h"
 
 namespace webrtc {
 
 namespace {
-// TODO(elad.alon): Subsequent CL experiments with PLR source.
-constexpr bool kUseTwccPlrForAna = false;
-
 class NullSmoothingFilter final : public SmoothingFilter {
  public:
   void AddSample(float sample) override {
     last_sample_ = rtc::Optional<float>(sample);
   }
 
   rtc::Optional<float> GetAverage() override { return last_sample_; }
 
   bool SetTimeConstantMs(int time_constant_ms) override {
     RTC_NOTREACHED();
@@ skipping 44 matching lines @@
   RTC_DCHECK_LE(
       GetPacketLossThreshold(config_.fec_enabling_threshold.high_bandwidth_bps,
                              config_.fec_disabling_threshold,
                              fec_disabling_threshold_info_),
       config_.fec_enabling_threshold.high_bandwidth_packet_loss);
 }
 
 FecControllerPlrBased::FecControllerPlrBased(const Config& config)
     : FecControllerPlrBased(
           config,
-          kUseTwccPlrForAna
+          webrtc::field_trial::FindFullName("UseTwccPlrForAna") == "Enabled"
               ? std::unique_ptr<NullSmoothingFilter>(new NullSmoothingFilter())
               : std::unique_ptr<SmoothingFilter>(
                     new SmoothingFilterImpl(config.time_constant_ms,
                                             config.clock))) {}
 
 FecControllerPlrBased::~FecControllerPlrBased() = default;
 
 void FecControllerPlrBased::UpdateNetworkMetrics(
     const NetworkMetrics& network_metrics) {
   if (network_metrics.uplink_bandwidth_bps)
@@ skipping 63 matching lines @@
   if (!uplink_bandwidth_bps_)
     return false;
   if (!packet_loss)
     return false;
   return *packet_loss <= GetPacketLossThreshold(*uplink_bandwidth_bps_,
                                                 config_.fec_disabling_threshold,
                                                 fec_disabling_threshold_info_);
 }
 
 }  // namespace webrtc