maintner: make godata.Get use locally cached data when network is unavailable

This is "Airplane mode". I had cached the latest maintner data before
a flight, but using godata.Get in flight failed when it tried to
update it.

Instead, detect the lack of network and just use whatever's available

Change-Id: Ieea29f844353377b3c36a531642a716f91f34436
Reviewed-by: Kevin Burke <>
1 file changed