Revert of Remove ignored return code from modules.

webrtc/modules/remote_bitrate_estimator/test/estimators/nada.cc

 /*
  *  Copyright (c) 2015 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 220 matching lines @@
   bitrate_kbps_ = std::min(bitrate_kbps_, kMaxBitrateKbps);
   bitrate_kbps_ = std::max(bitrate_kbps_, kMinBitrateKbps);
 
   observer_->OnNetworkChanged(1000 * bitrate_kbps_, 0, rtt_ms);
 }
 
 int64_t NadaBweSender::TimeUntilNextProcess() {
   return 100;
 }
 
-void NadaBweSender::Process() {
+int NadaBweSender::Process() {
+  return 0;
 }
 
 void NadaBweSender::AcceleratedRampUp(const NadaFeedback& fb) {
   const int kMaxRampUpQueuingDelayMs = 50;  // Referred as T_th.
   const float kGamma0 = 0.5f;               // Referred as gamma_0.
 
   float gamma =
       std::min(kGamma0, static_cast<float>(kMaxRampUpQueuingDelayMs) /
                             (min_round_trip_time_ms_ + min_feedback_delay_ms_));
 
@@ skipping 27 matching lines @@
                         (kTheta - (bitrate_kbps_ - kMinBitrateKbps) * x_hat)) /
                            (kTauOMs * kTauOMs) +
                        0.5f);
 
   bitrate_kbps_ = bitrate_kbps_ + smoothing_factor * original_increase;
 }
 
 }  // namespace bwe
 }  // namespace testing
 }  // namespace webrtc