GitLab

 - Update the dialog image.
 - Update the arguments to match the new UI.
 - Add information about story tags.

(To see how the markdown file will look, click the perf_trybots.md
file link and then click the "gitiles" link next to the patchset number.)

Bug: 1023451, 1059913
Change-Id: Ie019338f64d3fc0649cc7fd63d7a84bd29b756e0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2112579Reviewed-by: Wenbin Zhang <wenbinzhang@google.com>
Commit-Queue: Caleb Rouleau <crouleau@chromium.org>
Cr-Commit-Position: refs/heads/master@{#752612}