Fix data disabled icon from not showing in status bar

The NetworkController seemed to think the user wasn't set up since
the DeviceProvisionedController didn't send an initial callback
on add.

Also add some extra listening to data disabled state to avoid race
conditions there.

Change-Id: I17f759894a283da08eb0da7ceb5181355c8f4d55
Fixes: 35708363
Fixes: 35632846
Test: runtest systemui