Due to the locale dependent date format used here in strings that
neither matches en-US nor en-GB (in which the tests seem to be
executed) all tests failed, and then with passCount==0 the check
was

    If failCount <> 0 And passCount > 0 Then

instead of

    If failCount <> 0 Or passCount = 0 Then

so the end result was OK.

Also fixed the one case that was commented with
Rem why this fails in excel?
It actually also failed for us, just that because all tests failed
(see above) it never seemed to fail..
Problem seems to be the accuracy of the underlying date+time
double for this specific calculation. Good to know it happens in
Excel as well ;-)
As a workaround, conversion to string does the necessary rounding
internally.

Change-Id: If0302b2feab9e1233d66da4eccff732f61542a69
Reviewed-on: https://gerrit.libreoffice.org/45196Reviewed-by: Eike Rathke <erack@redhat.com>
Tested-by: Jenkins <ci@libreoffice.org>