Adding inherit-review-settings-ok to a subrepository causes the
PRESUBMIT.py of the parent repository to be run. In this case, the
CheckPatchFormatted() check needs to run "git cl format" with
CWD=repository root.

Bug: 768962

Change-Id: I44c642185efa78ba3a1bd752f94c3c09feff9cf1
Reviewed-on: https://chromium-review.googlesource.com/685355Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Andrew Grieve <agrieve@chromium.org>