[quartz/tests] Make tests run on everything lower then Vista (Try 2)

[Alexander Dorofeyev]

Paul Vriens wrote:
> Hi,
>
> RegDeleteTreeW is only available on Vista. (Were these tests run on 
> Windows to
> verify?).
Yes most of it was tested on XP, except this final registry cleanup 
thing, sorry my mistake.  Also it ran without errors with previous 
version of your patch on XP here.
>
> This version simply replaces the RegDeleteTree by a RegDeleteKey 
> (which is
> sufficient as there is only one value underneath the key).
This is not necessarily the case, Filtermapper's Register... methods add 
values and create subkeys in that key. I think it will have at least 
"Pins" subkey in the end. It was causing problms, until I found what I 
thought is a good safe and easy solution (RegDeleteTree). To ensure 
everything is removed, and especially if some Unregister.. calls fail 
for whatever reason, it really is preferable to do a recursive delete. 
If it takes copypasting a function then so be it. I think your previous 
patch was better, but maybe somebody noticed a problem with it, I don't 
know.