[MERGE] Hide the transport direction in the progress bar if it is unknown.

[Stephen J. Turnbull]

Jelmer Vernooij writes:

 > speeds/ETA are not necessarily correct anymore. X or = or >< makes more
 > sense to me (indicating bidirectional traffic).

"X" will very likely be misunderstood by Japanese, who universally use
it (even as a gesture in conversation) to mean "in conflict",
"erroneous", "unsuccessful", or simply "no".