commit 0c30d949df02680632ce1dd33fb67efe2f92b65f
author Lorenzo Colitti <lorenzo@google.com> Thu Mar 19 15:52:09 2020 +0000
committer Lorenzo Colitti <lorenzo@google.com> Thu Mar 19 15:54:05 2020 +0000
tree 383b74744be1be63e8bd7e62b7fb70b52491a1a5
parent 876e5e16a97b4fa2532cd1920da84e20bea31a68

Send tethered interface callbacks based on interface existence.

Currently, callbacks for tethered interface availability are sent
based on interface link state. This is incorrect:

- It is acceptable and expected to be able to enable tethering on
  an interface that does not yet have link up.
- It doesn't seem useful to disable Ethernet tethering if link
  temporarily goes down.

Instead, only base the callbacks on whether an interface exists
or not.

Bug: 150644681
Test: WIP tests in aosp/1260100 pass
Change-Id: I015219cbd03626c38fb5156d0cb2991ba7d7def7
Merged-In: I015219cbd03626c38fb5156d0cb2991ba7d7def7
(cherry picked from commit 64d12ea20ce3cd822518e0f15ed7483a2fb91a50)