Add global change ethernet state API am: e732c50882

Original change: https://android-review.googlesource.com/c/platform/frameworks/opt/net/ethernet/+/2027234

Change-Id: I03e8182db48c7adf327267ebcf1c2d649ee1fa2f
tree: 0d278ab1fdabf55ef5b6d55b9a19334d07f9bb6d
  1. service-t/
  2. tests/