[gtk: 1/2] GdkWin32: Add code for gtk-overlay-scrolling setting

[Luca Bacci <lbacci src gnome org>]

commit 83c780cfada42a78f4b18985f704c01ad4230631
Author: Luca Bacci <luca bacci982 gmail com>
Date:   Fri Jun 17 10:55:21 2022 +0200

    GdkWin32: Add code for gtk-overlay-scrolling setting
    
    Fixes https://gitlab.gnome.org/GNOME/gtk/-/issues/4899

 gdk/win32/gdkproperty-win32.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)
---
diff --git a/gdk/win32/gdkproperty-win32.c b/gdk/win32/gdkproperty-win32.c
index 0cbd3f0095..f919e53e9c 100644
--- a/gdk/win32/gdkproperty-win32.c
+++ b/gdk/win32/gdkproperty-win32.c
@@ -220,6 +220,19 @@ _gdk_win32_get_setting (const char *name,
 
       return TRUE;
     }
+  else if (strcmp ("gtk-overlay-scrolling", name) == 0)
+    {
+      DWORD val = 0;
+      DWORD sz = sizeof (val);
+      LSTATUS ret = 0;
+
+      ret = RegGetValueW (HKEY_CURRENT_USER, L"Control Panel\\Accessibility", L"DynamicScrollbars", 
RRF_RT_DWORD, NULL, &val, &sz);
+      if (ret == ERROR_SUCCESS)
+        {
+          g_value_set_boolean (value, val != 0);
+          return TRUE;
+        }
+    }
 
   return FALSE;
 }