A name record can be present but blank. In that case the blank
preferredFamily/preferredSubfamily shadowed a valid
fontFamily/fontSubfamily, so the metadata was discarded and the
filename fallback was used.
Select the first nonblank candidate with the new
first-nonblank-string helper before parsing, which keeps a valid
second candidate. The blank-candidate selection behaviour is adapted
from #11928 by CHOI JUNSOO.
Closes#10436
AI-assisted-by: muse-spark-1.3-contributor
Signed-off-by: CHOI JUNSOO <junsoo1172@gmail.com>
d1cddb5312