Fix for bug 8731235, flaky getting geolocation fix in tests

Instead of updating location once, start a background thread
updating the location every 250 ms.

It's not guaranteed that a single mock location update will
be seen be subsequent location observers, so updating location
in a loop ensures they receive it.

Change-Id: I93bdb2e94f54d99f350546e49facaea96a10a133
1 file changed