When we could not convert the UTF-8 sequence into Unicode for writing to
the Console, we should not try to write an insanely-long sequence of
invalid wide characters (mistaking the negative return value for an
unsigned length).
Reported by Coverity.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>