func handleJSON can call two failure completions

[timqzm]

Seems like a typo. Probably, return is missed after line 476.

[mariuskurgonas]

@timqzm

Thanks for catching this. Simple return will not do the trick because of then skipping churnLinks() call later. I will see about putting second half of the function into the do block and remove some of the fail completions as redundant.