After moving to Swarming, this bot executes in ~20 minutes instead of hours, making it a good candidate for pre-submit checks. It would have caught the leak that led to the revert in https://codereview.webrtc.org/2649113003/ if it would have run. BUG=chromium:497757 TBR=ehmaldonado@webrtc.org Review-Url: https://codereview.webrtc.org/2649353002 . Cr-Commit-Position: refs/heads/master@{#16226}