Make sysroot builds reproducible

BUG=913061
R=thestig
CC=jeremya

Change-Id: I40da9ac1fea6f23ed2cc3bf8d9a121cd9ed2be5b
Reviewed-on: https://chromium-review.googlesource.com/c/1378965
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Jeremy Apthorp <jeremya@chromium.org>
Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#616872}
4 files changed