SDL: Fix DefWindowProc called for events handled in WIN_WindowProc

SDL Commits
1 
From ef5b1c8f5fb7e7d0e6e4249bcc8b5083295dfea7 Mon Sep 17 00:00:00 2001
From: Daniel Ludwig <[EMAIL REDACTED]>
Date: Fri, 7 Nov 2025 11:00:55 +0100
Subject: [PATCH] Fix DefWindowProc called for events handled in WIN_WindowProc

---
 src/video/windows/SDL_windowswindow.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/video/windows/SDL_windowswindow.c b/src/video/windows/SDL_windowswindow.c
index 02ed14018ce3f..223020d2c66a9 100644
--- a/src/video/windows/SDL_windowswindow.c
+++ b/src/video/windows/SDL_windowswindow.c
@@ -427,16 +427,14 @@ static bool SetupWindowData(SDL_VideoDevice *_this, SDL_Window *window, HWND hwn
     // Set up the window proc function
 #ifdef GWLP_WNDPROC
     data->wndproc = (WNDPROC)GetWindowLongPtr(hwnd, GWLP_WNDPROC);
-    if (data->wndproc == WIN_WindowProc) {
+    if (data->wndproc == DefWindowProc) {
         data->wndproc = NULL;
-    } else {
         SetWindowLongPtr(hwnd, GWLP_WNDPROC, (LONG_PTR)WIN_WindowProc);
     }
 #else
     data->wndproc = (WNDPROC)GetWindowLong(hwnd, GWL_WNDPROC);
-    if (data->wndproc == WIN_WindowProc) {
+    if (data->wndproc == DefWindowProc) {
         data->wndproc = NULL;
-    } else {
         SetWindowLong(hwnd, GWL_WNDPROC, (LONG_PTR)WIN_WindowProc);
     }
 #endif