Use bayesian estimate of acked bitrate.

webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc

Index: webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc
diff --git a/webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc b/webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc
index a3a1893cbe23811e4baed231423bf17947865ca6..2aba8c0f3db791e0445f2348097890dbb786afd5 100644
--- a/webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc
+++ b/webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc
@@ -153,7 +153,8 @@ DelayBasedBweTest::DelayBasedBweTest()
       bitrate_estimator_(&clock_),
       stream_generator_(new test::StreamGenerator(1e6,  // Capacity.
                                                   clock_.TimeInMicroseconds())),
-      arrival_time_offset_ms_(0) {}
+      arrival_time_offset_ms_(0),
+      first_update_(true) {}
 
 DelayBasedBweTest::~DelayBasedBweTest() {}
 
@@ -219,8 +220,9 @@ bool DelayBasedBweTest::GenerateAndProcessFrame(uint32_t ssrc,
   if (result.updated) {
     bitrate_observer_.OnReceiveBitrateChanged({kDummySsrc},
                                               result.target_bitrate_bps);
-    if (result.target_bitrate_bps < bitrate_bps)
+    if (!first_update_ && result.target_bitrate_bps < bitrate_bps)
       overuse = true;
+    first_update_ = false;
   }
 
   clock_.AdvanceTimeMicroseconds(next_time_us - clock_.TimeInMicroseconds());
@@ -364,7 +366,6 @@ void DelayBasedBweTest::RateIncreaseRtpTimestampsTestHelper(
       bitrate_observer_.Reset();
     }
     ++iterations;
-    // ASSERT_LE(iterations, expected_iterations);
   }
   ASSERT_EQ(expected_iterations, iterations);
 }
@@ -488,7 +489,7 @@ void DelayBasedBweTest::TestWrappingHelper(int silence_time_s) {
   clock_.AdvanceTimeMilliseconds(silence_time_s * 1000);
   send_time_ms += silence_time_s * 1000;
 
-  for (size_t i = 0; i < 21; ++i) {
+  for (size_t i = 0; i < 22; ++i) {
     IncomingFeedback(clock_.TimeInMilliseconds(), send_time_ms,
                      sequence_number++, 1000);
     clock_.AdvanceTimeMilliseconds(2 * kFrameIntervalMs);