GitLab

If there is a diff, build.py will nuke the repository anyway. And in
pathological circumstances (see bug), printing the diff can take a very
long time.

Bug: 1014241
Change-Id: Ic045dfef66c7695b07ba9099352744d5becdcdfd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1862916Reviewed-by: Nico Weber <thakis@chromium.org>
Commit-Queue: Hans Wennborg <hans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#705937}