Move the TetheringRequest further up the stack.

Currently, the active TetheringRequest (if any) is fetched at the
very bottom of the stack, just before enabling the IpServer.
Have the callers pass it in instead.

This CL is a no-op refactor. In particular, it ignores the fact
that the TetheringRequest can be null, and that the connectivity
scope in the request might not match the requested state, etc. -
it just documents the current behaviour (bugs included) and
leaves it unchanged. It exists only to make future changes
easier.

Bug: 216524590
Test: covered by existing tests
Change-Id: Ie8af8b718a9de1f1d5adde0ac589060dce112a27
1 file changed