Alright.  I thought bug for bug compatibility was just for compatibility.  In this case it didn't seem like it mattered, and could be implemented differently between versions.

In that case, this patch can be ignored, and my previous patch can be used that does attempt to be the same as Windows.

The previous patch that I am referring to is:
user32: Increased area for scrolling via mouse drag outside scrollbar
http://www.winehq.org/pipermail/wine-devel/2008-May/065944.html

On Mon, May 26, 2008 at 2:53 PM, James Hawkins <truiken@gmail.com> wrote:
On Mon, May 26, 2008 at 1:46 PM, Dylan Smith <dylan.ah.smith@gmail.com> wrote:
> When dragging the scrollbar thumb with the mouse, the mouse is able to
> move away from the scrollbar and keep scrolling so long as it isn't too
> far away from the scrollbar.  This makes it easier to quickly scroll
> with the mouse.
>
> This patch is an alternative to the Windows approach of allowing the
> mouse to be dragged a certain distance from the scrollbar, and instead
> allows the mouse to be dragged any distance away and still scroll.
> Although this is different from Windows, it shouldn't result in any
> compatibility issues.
>
> It is my personal opinion that this is a simpler and more usable
> approach.
>

It doesn't matter if you think it's simpler and more usable.  We are
bug-for-bug compatible with Windows.

--
James Hawkins