Based on similar code in the call level scenario test framework. Bug: webrtc:10839 Change-Id: I262a890aa2cf905bb81b0f07957c08d0df5f7651 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/154745 Commit-Queue: Sebastian Jansson <srte@webrtc.org> Reviewed-by: Jonas Olsson <jonasolsson@webrtc.org> Cr-Commit-Position: refs/heads/master@{#29361}