GitLab

Also relands follow-up: Remove obsolete flags, code clean-up.

Original reviews:
https://chromium-review.googlesource.com/c/chromium/src/+/1694090
https://chromium-review.googlesource.com/c/chromium/src/+/1692492

Reason for reland:
* Now applies zipfile work-around to necessary scripts

Bug: 981974, 983519
Change-Id: Idce36ea6102302444bd77bebec4e3c1058db3161
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1711817
Commit-Queue: Andrew Grieve <agrieve@chromium.org>
Reviewed-by: Sam Maier <smaier@chromium.org>
Cr-Commit-Position: refs/heads/master@{#679861}