[automerger skipped] Make Ethernet interfaces more testable. am: fb336e9296 -s ours am: 523093a1ff -s ours am: 8f07511302 -s ours

am skip reason: Change-Id I86eef7a93267f800dbfc8eafd307effa76a344ca with SHA-1 fb336e9296 is in history

Change-Id: Iecf35ecae75b28c4bb529b9baf17121ef7e9dea2
tree: a02713025e69b8de6354fed91802b443f648442c
  1. service-t/
  2. tests/