p2p: Add p2p_ConsumeFiles test.

Add a new test that verifies a device can download a file from a
fake p2p peer.

BUG=chromium:271847
TEST=Ran this test with test_that on link
CQ-DEPEND=CL:170962,CL:171815,CL:171883

Change-Id: Ia62ef8f308e53d75ba2b7d14dde5d44292f6fca8
Reviewed-on: https://chromium-review.googlesource.com/171816
Reviewed-by: Chris Sosa <sosa@chromium.org>
Commit-Queue: Alex Deymo <deymo@chromium.org>
Tested-by: Alex Deymo <deymo@chromium.org>
3 files changed