remove inprocess tethering

It is just a constant source of bugs, with no real tests,
let's stop pretending this is a supported configuration.

The only tested configuration is out-of-process tethering
updatable apex.

Test: TreeHugger
Bug: 279942846
Change-Id: I4b659a3cd32b89a65549b56006b926a5ac755f7b
8 files changed