Add loss-based BWE estimate to the outgoing bitrate plot.

Review-Url: https://codereview.webrtc.org/2165523002
Cr-Commit-Position: refs/heads/master@{#13517}
diff --git a/webrtc/tools/event_log_visualizer/analyzer.h b/webrtc/tools/event_log_visualizer/analyzer.h
index 9b69ff1..0b92c10 100644
--- a/webrtc/tools/event_log_visualizer/analyzer.h
+++ b/webrtc/tools/event_log_visualizer/analyzer.h
@@ -67,6 +67,13 @@
     RTPHeader header;
   };
 
+  struct BwePacketLossEvent {
+    uint64_t timestamp;
+    int32_t new_bitrate;
+    uint8_t fraction_loss;
+    int32_t expected_packets;
+  };
+
   const ParsedRtcEventLog& parsed_log_;
 
   // A list of SSRCs we are interested in analysing.
@@ -78,6 +85,9 @@
   // if the stream has been configured.
   std::map<StreamId, std::vector<LoggedRtpPacket>> rtp_packets_;
 
+  // A list of all updates from the send-side loss-based bandwidth estimator.
+  std::vector<BwePacketLossEvent> bwe_loss_updates_;
+
   // Window and step size used for calculating moving averages, e.g. bitrate.
   // The generated data points will be |step_| microseconds apart.
   // Only events occuring at most |window_duration_| microseconds before the