Test implicit owners approval.

Change-Id: I1f38e1b931b191909659298a7e6e39c42603c1e0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2897275Reviewed-by: Yulan Lin <yulanlin@google.com>
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>