Rollback of "Use small BWE period when there is a true network degradation"

modules/remote_bitrate_estimator/aimd_rate_control.cc

Index: modules/remote_bitrate_estimator/aimd_rate_control.cc
diff --git a/modules/remote_bitrate_estimator/aimd_rate_control.cc b/modules/remote_bitrate_estimator/aimd_rate_control.cc
index d91f2cb342e80397df60d251836f2407d57967db..2daac01d216a53ca5334a3c92db921a3a6f86aac 100644
--- a/modules/remote_bitrate_estimator/aimd_rate_control.cc
+++ b/modules/remote_bitrate_estimator/aimd_rate_control.cc
@@ -136,12 +136,13 @@ int AimdRateControl::GetNearMaxIncreaseRateBps() const {
 }
 
 int AimdRateControl::GetExpectedBandwidthPeriodMs() const {
-  constexpr int kMinPeriodMs = 500;
+  constexpr int kMinPeriodMs = 2000;
+  constexpr int kDefaultPeriodMs = 3000;
   constexpr int kMaxPeriodMs = 50000;
 
   int increase_rate = GetNearMaxIncreaseRateBps();
   if (!last_decrease_)
-    return kMinPeriodMs;
+    return kDefaultPeriodMs;
 
   return std::min(kMaxPeriodMs,
                   std::max<int>(1000 * static_cast<int64_t>(*last_decrease_) /
@@ -210,17 +211,8 @@ uint32_t AimdRateControl::ChangeBitrate(uint32_t new_bitrate_bps,
 
       if (bitrate_is_initialized_ &&
           incoming_bitrate_bps < current_bitrate_bps_) {
-        constexpr float kDegradationFactor = 0.9f;
-        if (new_bitrate_bps <
-            kDegradationFactor * beta_ * current_bitrate_bps_) {
-          // If bitrate decreases more than a normal back off after overuse, it
-          // indicates a real network degradation. We do not let such a decrease
-          // to determine the bandwidth estimation period.
-          last_decrease_ = rtc::Optional<int>();
-        } else {
-          last_decrease_ = rtc::Optional<int>(
-              current_bitrate_bps_ - new_bitrate_bps);
-        }
+        last_decrease_ =
+            rtc::Optional<int>(current_bitrate_bps_ - new_bitrate_bps);
       }
       if (incoming_bitrate_kbps <
           avg_max_bitrate_kbps_ - 3 * std_max_bit_rate) {