Protect against invalid `statusTable`
Protect against invalid `statusTable`

iOS reported crashes at `fetchStatusTable()`. Analog to the checkup of
`sctable` before calling `fetchsc()`, the same should apply to the
status table too.

meganz/sdk,meganz/sdk,Acidburn0zzz/sdk,meganz/sdk,meganz/sdk,Acidburn0zzz/sdk,Acidburn0zzz/sdk,Acidburn0zzz/sdk,Acidburn0zzz/sdk,meganz/sdk,meganz/sdk,Acidburn0zzz/sdk,meganz/sdk,Acidburn0zzz/sdk,Acidburn0zzz/sdk