DDRAW: Fix reference counting

[Jakob Eriksson]

Stefan Dösinger wrote:

>Hello,
>
>  
>
>>In that case, it would be really beneficial with a unit test.
>>Both as documentation and to see what Windows does.
>>    
>>
>Excuse my ignorance, but what exactly is meant with 'unit test'? As far as 
>I've learned, it's a small piece of code which uses this functionality and 
>checks the results. My patch includes such a test:
>  
>

I'm sorry. The test looks excellent.

//Jakob