autotest: Add test for peer discovery

BUG=chromium:418738
TEST=This test passes against peerd with suitable functionality.

Change-Id: I8ea4b8269b7b0e908bb7bee65a1ecd2c8173cf6c
Reviewed-on: https://chromium-review.googlesource.com/224261
Reviewed-by: Christopher Wiley <wiley@chromium.org>
Commit-Queue: Christopher Wiley <wiley@chromium.org>
Tested-by: Christopher Wiley <wiley@chromium.org>
3 files changed