GitLab

The test was added in crrev.com/c/1446869 but has been flaky on Mac.
Also add "Pass" as an acceptable outcome for
RTCPeerConnection-track-stats.https.html.

TBR=rtoy@chromium.org

Bug: 929435
Change-Id: I37ef496d7d6f382ffad5dc8d75935d9faba8e225
Reviewed-on: https://chromium-review.googlesource.com/c/1457222
Commit-Queue: Takumi Fujimoto <takumif@chromium.org>
Auto-Submit: Takumi Fujimoto <takumif@chromium.org>
Reviewed-by: Takumi Fujimoto <takumif@chromium.org>
Cr-Commit-Position: refs/heads/master@{#629799}