[automerger skipped] Support setting the default interface to null again. am: 876e5e16a9 am: 65c1bc7c5d -s ours

am skip reason: Change-Id I5109d8da3aeb6c1f6523291d9e2ec92c64b5ad2d with SHA-1 876e5e16a9 is in history

Change-Id: Ie8adbc5239fdf8343a9b0e4cd30eddc28e96caaa
tree: 383b74744be1be63e8bd7e62b7fb70b52491a1a5
  1. service-t/
  2. tests/