WifiServiceImpl: setWifiApEnabled unit tests

Add unit tests to cover setWifiApEnabled.  This did require a small
change to check a tethering permission and add the user manager.

Bug: 37294233
Test: frameworks/opt/net/wifi/tests/wifitests/runtests.sh
Change-Id: I7bdfdcbdfa60605bc2e61f18aa8abeb4bcaf5c56
4 files changed
tree: 976294dee0f3b69e5c19f9423052560d283adef8
  1. libwifi_hal/
  2. libwifi_system/
  3. service/
  4. tests/
  5. PREUPLOAD.cfg