[Bug 54003] vbscript:run sometimes fails on Windows UTF-8 locales

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=54003

--- Comment #2 from Robert Wilhelm  ---
test failing is in api.vbs:

sub testChrError
    on error resume next

if isEnglishLang then
        call Err.clear()
        call Chr(-1)
        call ok(Err.number = 5, "Err.number = " & Err.number)

For en_AE_u8, isEnglishLang is true.
But for UTF-8 Chr(-1) is perfectly fine.

Maybe we should add something like isUTF8 to run.c and use it in this test.