When grep is called with the --quiet option, the pager is initialized
despite not being used. When the pager is "less", anything output by
previous commands and not ended with a newline is overwritten:
But prevent calling the pager in the first place, which would also
save an unnecessary fork().
Signed-off-by: Wilhelm Schuermann <wimschuermann@googlemail.com> Reviewed-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>