#2375 Fix scrolling speed on Windows with GTK3

[Enrico Tröger]

Users of Geany reported that vertical scrolling speed is too fast. See https://github.com/geany/geany/issues/2768 for details.

It turned out the attached patch seems to solve the problems on Windows.
Disclaimer: I do not fully understand the involved code and I can't test it realiably. I just created Geany binaries with those changes and users with the problem reported it worked for them. The changed code was a suggestion by Neil and Lex in the above linked Geany issue.

[Neil Hodgson]

Committed as [46d556].

[Jiri Techet]

FYI, this patch doesn't do the right thing. PLAT_GTK_WIN32 is always defined, it's just set to 0 on non-Windows platforms. This means that

#if (defined(__APPLE__) || defined(PLAT_GTK_WIN32)) && !defined(GDK_WINDOWING_QUARTZ)

always succeeds and the adaptive "wheel mouse intensity" code in the else branch is always skipped.

I discovered this while trying to improve the scrolling behavior in https://github.com/geany/geany/pull/4391 which I eventually plan to post as a patch once I test the code on more platforms.

[Neil Hodgson]

OK. So there is nothing for Scintilla to do at this point?