The steps are slow on dev workstations. Having them
run by the bots should be enough. The bots pass the mode
explicitly.

BUG=chromium:535160
LOG=n
TBR=tandrii@chromium.org, kjellander@chromium.org

Review URL: https://codereview.chromium.org/1738833002

Cr-Commit-Position: refs/heads/master@{#34290}