Refactoring: move ownership of RtcEventLog from Call to PeerConnection

webrtc/modules/bitrate_controller/send_side_bandwidth_estimation.cc

Index: webrtc/modules/bitrate_controller/send_side_bandwidth_estimation.cc
diff --git a/webrtc/modules/bitrate_controller/send_side_bandwidth_estimation.cc b/webrtc/modules/bitrate_controller/send_side_bandwidth_estimation.cc
index f306fb255dc060c386569e343b19199eada30ab8..d1a88355f18b5c0ae7e4eae2690d5685a5ded65f 100644
--- a/webrtc/modules/bitrate_controller/send_side_bandwidth_estimation.cc
+++ b/webrtc/modules/bitrate_controller/send_side_bandwidth_estimation.cc
@@ -75,7 +75,6 @@ SendSideBandwidthEstimation::SendSideBandwidthEstimation(RtcEventLog* event_log)
       last_rtc_event_log_ms_(-1),
       in_timeout_experiment_(webrtc::field_trial::FindFullName(
                                  "WebRTC-SendSideBwe") == "Enabled") {
-  RTC_DCHECK(event_log);
 }
 
 SendSideBandwidthEstimation::~SendSideBandwidthEstimation() {}
@@ -281,10 +280,10 @@ void SendSideBandwidthEstimation::UpdateEstimate(int64_t now_ms) {
     }
   }
   uint32_t capped_bitrate = CapBitrateToThresholds(now_ms, bitrate_);
-  if (capped_bitrate != bitrate_ ||
-      last_fraction_loss_ != last_logged_fraction_loss_ ||
-      last_rtc_event_log_ms_ == -1 ||
-      now_ms - last_rtc_event_log_ms_ > kRtcEventLogPeriodMs) {
+  if (event_log_ && (capped_bitrate != bitrate_ ||
+                     last_fraction_loss_ != last_logged_fraction_loss_ ||
+                     last_rtc_event_log_ms_ == -1 ||
+                     now_ms - last_rtc_event_log_ms_ > kRtcEventLogPeriodMs)) {
     event_log_->LogBwePacketLossEvent(capped_bitrate, last_fraction_loss_,
                                       expected_packets_since_last_loss_update_);
     last_logged_fraction_loss_ = last_fraction_loss_;