When processItems filled the last free transfer slot it checked the
next queued item's expiry before the transfer limit, so if that
expiry was still fractionally in the future the timer was reset
instead of stopped. This caused intermittent failures in
TestWriteBackMaxQueue which asserts the timer is stopped once
--transfers uploads are in progress.
Check the transfer limit first so the timer is always stopped when
the transfer limit is reached. The timer is restarted when an upload
finishes so nothing stalls.
Also fix a typo in TestWriteBackMaxQueue which named every queued
item "number1".
Nick Craig-Wood
c851d4dec5