This change adds incoming & outgoing packet rates to the event_log_visualizer. The outgoing packet rate is drawn on the graph with outgoing RTP rate, because we want to see it together with bandwidth estimate and probe clusters. The incoming packet rate is drawn separately. Bug: webrtc:9719 Change-Id: I32648d016359af110837440ed1a5f9c31c841ea7 Reviewed-on: https://webrtc-review.googlesource.com/c/122941 Reviewed-by: Björn Terelius <terelius@webrtc.org> Reviewed-by: Bjorn Mellem <mellem@webrtc.org> Commit-Queue: Peter Slatala <psla@webrtc.org> Cr-Commit-Position: refs/heads/master@{#26696}