Turn off WifiTetherSettings page.

Merged-In: If92798ddf075801e66cd97ecacff2f8df1e41985
Change-Id: Idab770509a8049907a256cce2b8f00f236c2dbdc
Fixes: 65852564
Test: rerun robotests
Test: new instrumentation test to check flag initial state
3 files changed