Remove unused loss based param.

Bug: webrtc:12707
Change-Id: Ie6f8eac23a4fb2fbd648b2a213319af508c40230
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/324045
Commit-Queue: Diep Bui <diepbp@webrtc.org>
Reviewed-by: Per Kjellander <perkj@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40967}

modules/congestion_controller/goog_cc/loss_based_bwe_v2.cc

diff --git a/modules/congestion_controller/goog_cc/loss_based_bwe_v2.cc b/modules/congestion_controller/goog_cc/loss_based_bwe_v2.cc
index 4bcae9d..c0d7d10 100644
--- a/modules/congestion_controller/goog_cc/loss_based_bwe_v2.cc
+++ b/modules/congestion_controller/goog_cc/loss_based_bwe_v2.cc
@@ -394,8 +394,6 @@
   FieldTrialParameter<double> max_increase_factor("MaxIncreaseFactor", 1.3);
   FieldTrialParameter<TimeDelta> delayed_increase_window(
       "DelayedIncreaseWindow", TimeDelta::Millis(300));
-  FieldTrialParameter<bool> use_acked_bitrate_only_when_overusing(
-      "UseAckedBitrateOnlyWhenOverusing", false);
   FieldTrialParameter<bool>
       not_increase_if_inherent_loss_less_than_average_loss(
           "NotIncreaseIfInherentLossLessThanAverageLoss", true);
@@ -439,7 +437,6 @@
                      &bandwidth_backoff_lower_bound_factor,
                      &max_increase_factor,
                      &delayed_increase_window,
-                     &use_acked_bitrate_only_when_overusing,
                      &not_increase_if_inherent_loss_less_than_average_loss,
                      &high_loss_rate_threshold,
                      &bandwidth_cap_at_high_loss_rate,
@@ -496,8 +493,6 @@
       bandwidth_backoff_lower_bound_factor.Get();
   config->max_increase_factor = max_increase_factor.Get();
   config->delayed_increase_window = delayed_increase_window.Get();
-  config->use_acked_bitrate_only_when_overusing =
-      use_acked_bitrate_only_when_overusing.Get();
   config->not_increase_if_inherent_loss_less_than_average_loss =
       not_increase_if_inherent_loss_less_than_average_loss.Get();
   config->high_loss_rate_threshold = high_loss_rate_threshold.Get();

modules/congestion_controller/goog_cc/loss_based_bwe_v2.h

diff --git a/modules/congestion_controller/goog_cc/loss_based_bwe_v2.h b/modules/congestion_controller/goog_cc/loss_based_bwe_v2.h
index aba70b0..9be8341 100644
--- a/modules/congestion_controller/goog_cc/loss_based_bwe_v2.h
+++ b/modules/congestion_controller/goog_cc/loss_based_bwe_v2.h
@@ -109,7 +109,6 @@
     double bandwidth_backoff_lower_bound_factor = 0.0;
     double max_increase_factor = 0.0;
     TimeDelta delayed_increase_window = TimeDelta::Zero();
-    bool use_acked_bitrate_only_when_overusing = false;
     bool not_increase_if_inherent_loss_less_than_average_loss = false;
     double high_loss_rate_threshold = 1.0;
     DataRate bandwidth_cap_at_high_loss_rate = DataRate::MinusInfinity();