server: allow OpenClipboard to succeed when already open

[Eric Frias]

James Hawkins wrote:

> On 2/7/06, Eric Frias <efrias at syncad.com> wrote: 
>
>> I think I submitted a version
>> of this patch a year or two back, but it wasn't accepted.   
>
> You should add a unit test for this case in Wine's test suite.  It
> would be pretty easy to write, and it would verify this information,
> making your fix more likely to be accepted.

Yeah, I didn't write a test on first go-around and I didn't follow up, 
so I'm not entirely surprised that the patch didn't get accepted.  This 
is the first time I've tried to write a test, and I was pleased to find 
out that it was easy to do and the documentation on test-writing and 
compiling was accurate.

Eric