Trackbar select range tweaks

[Duane Clark]

BiGgUn wrote:
>> Changelog: Oops, initial thumb length doesn't appear to depend on 
>> SM_CYCAPTION after all.
> 
> 
> Thumb length DOES depend on GetSystemMetrics( SM_CYCAPTION) on a
> native platform. ( thumb_length = GetSystemMetrics( SM_CYCAPTION) + 2
> [with no select range]) If wine uses standard values from windows
> there's no matter. But if a user decides to change these values in
> its registry, trackbars won't reflect those changes in their sizes.
> 
> So i think that thumb length still need to depend on this metrics
> value.

Well, as I mentioned elsewhere, on Win2K for me
GetSystemMetrics(SM_CYCAPTION) returns 20, while the initial thumb size
is 21. So any relationship appears to depend on the Windows version.

By all means feel free to figure out exactly how it works, and submit a 
patch. But I think it needs to be tested on a few different versions of 
Windows. I find the explanation of SM_CYCAPTION in the SDK to not be too 
clear:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/win9x/verdiff_8hwz.asp