Otherwise it spends half of the time doing timezone conversions to local time.
- Copied a million files. Time spent in QDateTime::setMSecsSinceEpoch went from 44% to 0.1%, total time of addCopyInfoFromUDSEnty went from 57% to 36%, now the bottleneck is all that path concatenation causing URL decoding.
- Verified that copied files still have correct mtime
- Verified that "overwrite?" dialog still shows correct mtime