It was possible for the a previous write / part to fail or be aborted
and the next part write still happened. This causes a data ordering
corruption.
The whole write to parallel stdout fails, so there shouldn't be
confusion with regards to the output acceptability. However, it would
be clearer, if we avoided writing out-of-order data... mainly to be
clear that we didn't corrupt the data, just that it's incomplete.
Change-Id: I97b0d14404f29e8615e7d29b10cbd61ccb861e40