Now with correct error handling.

R=nodir@chromium.org, vadimsh@chromium.org

Bug: 869227
Change-Id: I961fd80209c9d9988e9d03016b7c0bd253c6cdfb
Reviewed-on: https://chromium-review.googlesource.com/c/1347249
Commit-Queue: Robbie Iannucci <iannucci@chromium.org>
Commit-Queue: Vadim Shtayura <vadimsh@chromium.org>
Auto-Submit: Robbie Iannucci <iannucci@chromium.org>
Reviewed-by: Vadim Shtayura <vadimsh@chromium.org>