GitLab

This flag is no longer needed by the perf testing infrastructure and can be
misused for malicious purposes, so remove it.

BUG=none
TEST=none

Change-Id: Iaa875bc887a5a1564ca10ef7d3c2d760a1f7cb11
Reviewed-on: https://chromium-review.googlesource.com/857604Reviewed-by: Pavel Feldman <pfeldman@chromium.org>
Reviewed-by: Egor Pasko <pasko@chromium.org>
Commit-Queue: Peter Kasting <pkasting@chromium.org>
Cr-Commit-Position: refs/heads/master@{#528386}