Treat clock updates to never add a negative usage window.

Bug: 899980
Change-Id: I196999915290fe07322d934423430a0782c7ba55
Reviewed-on: https://chromium-review.googlesource.com/c/1330224
Reviewed-by: Sergey Poromov <poromov@chromium.org>
Commit-Queue: Henrique Grandinetti <hgrandinetti@chromium.org>
Cr-Commit-Position: refs/heads/master@{#607732}
2 files changed