This can be better used to determine the length of test calls,
rather than using the interval metric.
Bug: webrtc:11017
Change-Id: I69f66fa750b061a7d010d591a718555e2b5b34b7
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/156087
Commit-Queue: Evan Shrubsole <eshr@google.com>
Reviewed-by: Sebastian Jansson <srte@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29413}
