Add tests for the PacketKeepalive API.

This currently fails in many different ways, but it tells us what
to fix.

Bug: 22606153
Bug: 23884210
Change-Id: If2e5ee0a8d7b26cad67d3d566ed5b1383e0db096
2 files changed
tree: b932fee5e62d6a558d0f31f091b4930e2e5d7b8c
  1. core/
  2. services/
  3. tests/