Revert of Enable the bayesian bitrate estimator by default. (patchset #5 id:80001 of https://codereview.webrtc.org/2749803002/ )

Reason for revert:
Looks like this has caused multiple Android webrtc perf build bot failures in RampUpTest.UpDownUpTransportSequenceNumberRtx

Original issue's description:
> Enable the bayesian bitrate estimator by default.
>
> BUG=webrtc:6566, webrtc:7415
>
> Review-Url: https://codereview.webrtc.org/2749803002
> Cr-Commit-Position: refs/heads/master@{#17475}
> Committed: c53a17f28e

TBR=terelius@webrtc.org,magjed@webrtc.org,stefan@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6566, webrtc:7415

Review-Url: https://codereview.webrtc.org/2786913003
Cr-Commit-Position: refs/heads/master@{#17476}

webrtc/call/rampup_tests.cc

@@ -25,7 +25,6 @@ static const int kExpectedHighVideoBitrateBps = 80000;
 static const int kExpectedHighAudioBitrateBps = 30000;
 static const int kLowBandwidthLimitBps = 20000;
 static const int kExpectedLowBitrateBps = 20000;
-static const int kUnlimitedCapacityBps = 10000000;
 
 std::vector<uint32_t> GenerateSsrcs(size_t num_streams, uint32_t ssrc_offset) {
   std::vector<uint32_t> ssrcs;
@@ -418,9 +417,8 @@ RampUpDownUpTester::RampUpDownUpTester(size_t num_video_streams,
                    rtx,
                    red,
                    report_perf_stats),
-      link_rates_({GetExpectedHighBitrate() / 1000,
-                   kLowBandwidthLimitBps / 1000, kUnlimitedCapacityBps / 1000,
-                   0}),
+      link_rates_({GetHighLinkCapacity(), kLowBandwidthLimitBps / 1000,
+                   GetHighLinkCapacity(), 0}),
       test_state_(kFirstRampup),
       next_state_(kTransitionToNextState),
       state_start_ms_(clock_->TimeInMilliseconds()),
@@ -490,6 +488,10 @@ int RampUpDownUpTester::GetExpectedHighBitrate() const {
   return expected_bitrate_bps;
 }
 
+int RampUpDownUpTester::GetHighLinkCapacity() const {
+  return 4 * GetExpectedHighBitrate() / (3 * 1000);
+}
+
 size_t RampUpDownUpTester::GetFecBytes() const {
   size_t flex_fec_bytes = 0;
   if (num_flexfec_streams_ > 0) {

webrtc/examples/objc/AppRTCMobile/ios/ARDAppDelegate.m

@@ -26,6 +26,7 @@
 - (BOOL)application:(UIApplication *)application
     didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
   NSDictionary *fieldTrials = @{
+    kRTCFieldTrialImprovedBitrateEstimateKey: kRTCFieldTrialEnabledValue,
     kRTCFieldTrialH264HighProfileKey: kRTCFieldTrialEnabledValue,
   };
   RTCInitFieldTrialDictionary(fieldTrials);

webrtc/modules/congestion_controller/delay_based_bwe.cc

@@ -52,9 +52,14 @@ constexpr double kDefaultMedianSlopeThresholdGain = 4.0;
 
 constexpr int kMaxConsecutiveFailedLookups = 5;
 
+const char kBitrateEstimateExperiment[] = "WebRTC-ImprovedBitrateEstimate";
 const char kBweTrendlineFilterExperiment[] = "WebRTC-BweTrendlineFilter";
 const char kBweMedianSlopeFilterExperiment[] = "WebRTC-BweMedianSlopeFilter";
 
+bool BitrateEstimateExperimentIsEnabled() {
+  return webrtc::field_trial::IsEnabled(kBitrateEstimateExperiment);
+}
+
 bool TrendlineFilterExperimentIsEnabled() {
   std::string experiment_string =
       webrtc::field_trial::FindFullName(kBweTrendlineFilterExperiment);
@@ -148,9 +153,19 @@ DelayBasedBwe::BitrateEstimator::BitrateEstimator()
       current_win_ms_(0),
       prev_time_ms_(-1),
       bitrate_estimate_(-1.0f),
-      bitrate_estimate_var_(50.0f) {}
+      bitrate_estimate_var_(50.0f),
+      old_estimator_(kBitrateWindowMs, 8000),
+      in_experiment_(BitrateEstimateExperimentIsEnabled()) {}
 
 void DelayBasedBwe::BitrateEstimator::Update(int64_t now_ms, int bytes) {
+  if (!in_experiment_) {
+    old_estimator_.Update(bytes, now_ms);
+    rtc::Optional<uint32_t> rate = old_estimator_.Rate(now_ms);
+    bitrate_estimate_ = -1.0f;
+    if (rate)
+      bitrate_estimate_ = *rate / 1000.0f;
+    return;
+  }
   int rate_window_ms = kRateWindowMs;
   // We use a larger window at the beginning to get a more stable sample that
   // we can use to initialize the estimate.

webrtc/modules/congestion_controller/delay_based_bwe.h

@@ -17,6 +17,7 @@
 
 #include "webrtc/base/checks.h"
 #include "webrtc/base/constructormagic.h"
+#include "webrtc/base/rate_statistics.h"
 #include "webrtc/base/thread_checker.h"
 #include "webrtc/modules/congestion_controller/median_slope_estimator.h"
 #include "webrtc/modules/congestion_controller/probe_bitrate_estimator.h"
@@ -76,6 +77,8 @@ class DelayBasedBwe {
     int64_t prev_time_ms_;
     float bitrate_estimate_;
     float bitrate_estimate_var_;
+    RateStatistics old_estimator_;
+    const bool in_experiment_;
   };
 
   Result IncomingPacketFeedback(const PacketFeedback& packet_feedback);

webrtc/modules/congestion_controller/delay_based_bwe_unittest.cc

@@ -119,7 +119,7 @@ TEST_F(DelayBasedBweTest, ProbeDetectionSlowerArrivalHighBitrate) {
 TEST_F(DelayBasedBweTest, GetProbingInterval) {
   int64_t default_interval_ms = bitrate_estimator_->GetProbingIntervalMs();
   EXPECT_GT(default_interval_ms, 0);
-  CapacityDropTestHelper(1, true, 333, 0);
+  CapacityDropTestHelper(1, true, 567, 0);
   int64_t interval_ms = bitrate_estimator_->GetProbingIntervalMs();
   EXPECT_GT(interval_ms, 0);
   EXPECT_NE(interval_ms, default_interval_ms);
@@ -134,23 +134,23 @@ TEST_F(DelayBasedBweTest, RateIncreaseReordering) {
 }
 
 TEST_F(DelayBasedBweTest, RateIncreaseRtpTimestamps) {
-  RateIncreaseRtpTimestampsTestHelper(1288);
+  RateIncreaseRtpTimestampsTestHelper(1240);
 }
 
 TEST_F(DelayBasedBweTest, CapacityDropOneStream) {
-  CapacityDropTestHelper(1, false, 333, 0);
+  CapacityDropTestHelper(1, false, 567, 0);
 }
 
 TEST_F(DelayBasedBweTest, CapacityDropPosOffsetChange) {
-  CapacityDropTestHelper(1, false, 300, 30000);
+  CapacityDropTestHelper(1, false, 200, 30000);
 }
 
 TEST_F(DelayBasedBweTest, CapacityDropNegOffsetChange) {
-  CapacityDropTestHelper(1, false, 300, -30000);
+  CapacityDropTestHelper(1, false, 733, -30000);
 }
 
 TEST_F(DelayBasedBweTest, CapacityDropOneStreamWrap) {
-  CapacityDropTestHelper(1, true, 333, 0);
+  CapacityDropTestHelper(1, true, 567, 0);
 }
 
 TEST_F(DelayBasedBweTest, TestTimestampGrouping) {
@@ -172,6 +172,37 @@ TEST_F(DelayBasedBweTest, TestLongTimeoutAndWrap) {
   TestWrappingHelper(10 * 64);
 }
 
+class DelayBasedBweExperimentTest : public DelayBasedBweTest {
+ public:
+  DelayBasedBweExperimentTest()
+      : override_field_trials_("WebRTC-ImprovedBitrateEstimate/Enabled/") {
+    bitrate_estimator_.reset(new DelayBasedBwe(nullptr, &clock_));
+  }
+
+ private:
+  test::ScopedFieldTrials override_field_trials_;
+};
+
+TEST_F(DelayBasedBweExperimentTest, RateIncreaseRtpTimestamps) {
+  RateIncreaseRtpTimestampsTestHelper(1288);
+}
+
+TEST_F(DelayBasedBweExperimentTest, CapacityDropOneStream) {
+  CapacityDropTestHelper(1, false, 333, 0);
+}
+
+TEST_F(DelayBasedBweExperimentTest, CapacityDropPosOffsetChange) {
+  CapacityDropTestHelper(1, false, 300, 30000);
+}
+
+TEST_F(DelayBasedBweExperimentTest, CapacityDropNegOffsetChange) {
+  CapacityDropTestHelper(1, false, 300, -30000);
+}
+
+TEST_F(DelayBasedBweExperimentTest, CapacityDropOneStreamWrap) {
+  CapacityDropTestHelper(1, true, 333, 0);
+}
+
 class DelayBasedBweTrendlineExperimentTest : public DelayBasedBweTest {
  public:
   DelayBasedBweTrendlineExperimentTest()
@@ -184,11 +215,11 @@ class DelayBasedBweTrendlineExperimentTest : public DelayBasedBweTest {
 };
 
 TEST_F(DelayBasedBweTrendlineExperimentTest, RateIncreaseRtpTimestamps) {
-  RateIncreaseRtpTimestampsTestHelper(1288);
+  RateIncreaseRtpTimestampsTestHelper(1240);
 }
 
 TEST_F(DelayBasedBweTrendlineExperimentTest, CapacityDropOneStream) {
-  CapacityDropTestHelper(1, false, 433, 0);
+  CapacityDropTestHelper(1, false, 600, 0);
 }
 
 TEST_F(DelayBasedBweTrendlineExperimentTest, CapacityDropPosOffsetChange) {
@@ -196,11 +227,11 @@ TEST_F(DelayBasedBweTrendlineExperimentTest, CapacityDropPosOffsetChange) {
 }
 
 TEST_F(DelayBasedBweTrendlineExperimentTest, CapacityDropNegOffsetChange) {
-  CapacityDropTestHelper(1, false, 767, -30000);
+  CapacityDropTestHelper(1, false, 1267, -30000);
 }
 
 TEST_F(DelayBasedBweTrendlineExperimentTest, CapacityDropOneStreamWrap) {
-  CapacityDropTestHelper(1, true, 433, 0);
+  CapacityDropTestHelper(1, true, 600, 0);
 }
 
 class DelayBasedBweMedianSlopeExperimentTest : public DelayBasedBweTest {
@@ -215,11 +246,11 @@ class DelayBasedBweMedianSlopeExperimentTest : public DelayBasedBweTest {
 };
 
 TEST_F(DelayBasedBweMedianSlopeExperimentTest, RateIncreaseRtpTimestamps) {
-  RateIncreaseRtpTimestampsTestHelper(1288);
+  RateIncreaseRtpTimestampsTestHelper(1240);
 }
 
 TEST_F(DelayBasedBweMedianSlopeExperimentTest, CapacityDropOneStream) {
-  CapacityDropTestHelper(1, false, 367, 0);
+  CapacityDropTestHelper(1, false, 600, 0);
 }
 
 TEST_F(DelayBasedBweMedianSlopeExperimentTest, CapacityDropPosOffsetChange) {
@@ -227,11 +258,11 @@ TEST_F(DelayBasedBweMedianSlopeExperimentTest, CapacityDropPosOffsetChange) {
 }
 
 TEST_F(DelayBasedBweMedianSlopeExperimentTest, CapacityDropNegOffsetChange) {
-  CapacityDropTestHelper(1, false, 767, -30000);
+  CapacityDropTestHelper(1, false, 1267, -30000);
 }
 
 TEST_F(DelayBasedBweMedianSlopeExperimentTest, CapacityDropOneStreamWrap) {
-  CapacityDropTestHelper(1, true, 367, 0);
+  CapacityDropTestHelper(1, true, 600, 0);
 }
 
 }  // namespace webrtc

webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc

@@ -411,7 +411,7 @@ void DelayBasedBweTest::CapacityDropTestHelper(
   uint32_t bitrate_bps = SteadyStateRun(
       kDefaultSsrc, steady_state_time * kFramerate, kStartBitrate,
       kMinExpectedBitrate, kMaxExpectedBitrate, kInitialCapacityBps);
-  EXPECT_NEAR(kInitialCapacityBps, bitrate_bps, 150000u);
+  EXPECT_NEAR(kInitialCapacityBps, bitrate_bps, 130000u);
   bitrate_observer_.Reset();
 
   // Add an offset to make sure the BWE can handle it.

webrtc/sdk/objc/Framework/Classes/RTCFieldTrials.mm

@@ -20,6 +20,7 @@ NSString * const kRTCFieldTrialAudioSendSideBweKey = @"WebRTC-Audio-SendSideBwe"
 NSString * const kRTCFieldTrialSendSideBweWithOverheadKey = @"WebRTC-SendSideBwe-WithOverhead";
 NSString * const kRTCFieldTrialFlexFec03AdvertisedKey = @"WebRTC-FlexFEC-03-Advertised";
 NSString * const kRTCFieldTrialFlexFec03Key = @"WebRTC-FlexFEC-03";
+NSString * const kRTCFieldTrialImprovedBitrateEstimateKey = @"WebRTC-ImprovedBitrateEstimate";
 NSString * const kRTCFieldTrialMedianSlopeFilterKey = @"WebRTC-BweMedianSlopeFilter";
 NSString * const kRTCFieldTrialTrendlineFilterKey = @"WebRTC-BweTrendlineFilter";
 NSString * const kRTCFieldTrialH264HighProfileKey = @"WebRTC-H264HighProfile";

webrtc/sdk/objc/Framework/Headers/WebRTC/RTCFieldTrials.h

@@ -17,6 +17,7 @@ RTC_EXTERN NSString * const kRTCFieldTrialAudioSendSideBweKey;
 RTC_EXTERN NSString * const kRTCFieldTrialSendSideBweWithOverheadKey;
 RTC_EXTERN NSString * const kRTCFieldTrialFlexFec03AdvertisedKey;
 RTC_EXTERN NSString * const kRTCFieldTrialFlexFec03Key;
+RTC_EXTERN NSString * const kRTCFieldTrialImprovedBitrateEstimateKey;
 RTC_EXTERN NSString * const kRTCFieldTrialH264HighProfileKey;
 
 /** The valid value for field trials above. */