Fix bug introduced at b4cf9011ff for osm import-history

Commit b4cf9011ff06cf94b1fb2531ca3f8feb0d2efdf8 replaced
 listener.setCanceled(false);listener.progress(0f);
by
 listener.cancel();listener.setProgress(0f);
In OsmHistoryImport.commit(...) which made the commit
op for each changeset think the operation was cancelled
and hence no commit was performed at all.