Only log BWE updates if the actual estimate changed or if we have non-zero loss reports.

webrtc/modules/bitrate_controller/send_side_bandwidth_estimation_unittest.cc

 /*
  *  Copyright (c) 2014 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 49 matching lines @@
 }
 
 TEST(SendSideBweTest, InitialDelayBasedBweWithProbing) {
   TestProbing(true);
 }
 
 TEST(SendSideBweTest, DoesntReapplyBitrateDecreaseWithoutFollowingRemb) {
   MockRtcEventLog event_log;
   EXPECT_CALL(event_log,
               LogBwePacketLossEvent(testing::Gt(0), testing::Gt(0), 0))
-      .Times(3);
+      .Times(1);
   SendSideBandwidthEstimation bwe(&event_log);
   static const int kMinBitrateBps = 100000;
   static const int kInitialBitrateBps = 1000000;
   bwe.SetMinMaxBitrate(kMinBitrateBps, 1500000);
   bwe.SetSendBitrate(kInitialBitrateBps);
 
   static const uint8_t kFractionLoss = 128;
   static const int64_t kRttMs = 50;
 
   int64_t now_ms = 0;
@@ skipping 30 matching lines @@
   bwe.UpdateEstimate(now_ms);
   bwe.CurrentEstimate(&bitrate_bps, &fraction_loss, &rtt_ms);
 
   EXPECT_EQ(last_bitrate_bps, bitrate_bps);
   // The old loss rate should still be applied though.
   EXPECT_EQ(kFractionLoss, fraction_loss);
   EXPECT_EQ(kRttMs, rtt_ms);
 }
 
 }  // namespace webrtc