Fixed building with the video subsystem disabled

src/core/windows/SDL_windows.c

@@ -436,48 +436,3 @@ DECLSPEC int MINGW32_FORCEALIGN SDL_RunApp(int _argc, char* _argv[], SDL_main_fu
 #endif /* __WIN32__ */
 
 #endif /* defined(__WIN32__) || defined(__WINRT__) || defined(__GDK__) */
-
-/*
- * Public APIs
- */
-#ifndef SDL_VIDEO_DRIVER_WINDOWS
-
-#if defined(__WIN32__) || defined(__GDK__)
-int SDL_RegisterApp(const char *name, Uint32 style, void *hInst)
-{
-    (void)name;
-    (void)style;
-    (void)hInst;
-    return 0;
-}
-
-void SDL_UnregisterApp(void)
-{
-}
-
-void SDL_SetWindowsMessageHook(SDL_WindowsMessageHook callback, void *userdata)
-{
-}
-#endif /* __WIN32__ || __GDK__ */
-
-#if defined(__WIN32__) || defined(__WINGDK__)
-int SDL_Direct3D9GetAdapterIndex(SDL_DisplayID displayID)
-{
-    (void)displayID;
-    return 0; /* D3DADAPTER_DEFAULT */
-}
-
-SDL_bool SDL_DXGIGetOutputInfo(SDL_DisplayID displayID, int *adapterIndex, int *outputIndex)
-{
-    (void)displayID;
-    if (adapterIndex) {
-        *adapterIndex = -1;
-    }
-    if (outputIndex) {
-        *outputIndex = -1;
-    }
-    return SDL_FALSE;
-}
-#endif /* __WIN32__ || __WINGDK__ */
-
-#endif /* !SDL_VIDEO_DRIVER_WINDOWS */