Location Wi-Fi scanning should not be turned off when the screen turns off.
Bug: 113876483
Test: Run CTS, manually toggle location Wi-Fi scanning off right after the screen
turns on and observe failure.
Test: Run CTS with location Wi-Fi scanning initially turned off and observe failure.
Test: Run CTS with location Wi-Fi scanning initially turned on and observe
success.
Change-Id: I092a3854b6365de72c2cfe38a55a0e1cedfcabd9