It is failing on writing out the perf result files but it is running and uploading to the dashboard.  I am investigating.

The same issue is happening with mac 10.12

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/933e64e8d889dbe40b69074038b09e67892551d4

commit 933e64e8d889dbe40b69074038b09e67892551d4
Author: Emily Hanley <eyaich@google.com>
Date: Mon Jul 02 14:49:31 2018

Reland parallelizing perf dashboard uploads

Failures in this revert https://chromium-review.googlesource.com/c/chromium/src/+/1120125
were for failing mac, but the everything was succeeding, we were
failing when trying to right out not valid json as perf results.

I have added logic in line 447 of process_perf_results.py to catch
these errors in the future.  Note this was also an issue in the old
recipe, it just shows one step as failed instead of the entire suite.

Bug:  713357 , 854162 ,  859073 , 858995
Change-Id: I37c8f8fe3d7973962a17bbd64b758c7c98517799
Reviewed-on: https://chromium-review.googlesource.com/1122478
Reviewed-by: Ned Nguyen <nednguyen@google.com>
Commit-Queue: Emily Hanley <eyaich@chromium.org>
Cr-Commit-Position: refs/heads/master@{#571893}
[modify] https://crrev.com/933e64e8d889dbe40b69074038b09e67892551d4/tools/perf/core/oauth_api.py
[modify] https://crrev.com/933e64e8d889dbe40b69074038b09e67892551d4/tools/perf/core/results_dashboard.py
[modify] https://crrev.com/933e64e8d889dbe40b69074038b09e67892551d4/tools/perf/process_perf_results.py