wayland: Only restore windowed constraints in configuration events

In some cases, the fullscreen deadline handler can be hit before the associated configure event is received, resulting in the constraints being erroneously restored. The state is doubled buffered, so it shouldn't interfere with the pending fullscreen dimensions, but it isn't correct behavior.

According to the spec, calls to set/unset fullscreen will always have an associated configure event, and the constraints will be reapplied as needed there.

src/video/wayland/SDL_waylandwindow.c

@@ -474,7 +474,6 @@ static void fullscreen_deadline_handler(void *data, struct wl_callback *callback
 
     if (window && window->driverdata) {
         window->driverdata->fullscreen_deadline_count--;
-        SetMinMaxDimensions(window);
     }
 
     wl_callback_destroy(callback);
@@ -1983,24 +1982,6 @@ int Wayland_FlashWindow(SDL_VideoDevice *_this, SDL_Window *window, SDL_FlashOpe
     return 0;
 }
 
-static void fullscreen_configure_handler(void *data, struct wl_callback *callback, uint32_t callback_data)
-{
-    /* Get the window from the ID as it may have been destroyed */
-    SDL_WindowID windowID = (SDL_WindowID)((uintptr_t)data);
-    SDL_Window *window = SDL_GetWindowFromID(windowID);
-
-    if (window && window->driverdata && window->driverdata->is_fullscreen) {
-        ConfigureWindowGeometry(window);
-        CommitLibdecorFrame(window);
-    }
-
-    wl_callback_destroy(callback);
-}
-
-static struct wl_callback_listener fullscreen_configure_listener = {
-    fullscreen_configure_handler
-};
-
 int Wayland_SetWindowFullscreen(SDL_VideoDevice *_this, SDL_Window *window,
                                  SDL_VideoDisplay *display, SDL_bool fullscreen)
 {
@@ -2041,9 +2022,8 @@ int Wayland_SetWindowFullscreen(SDL_VideoDevice *_this, SDL_Window *window,
             wind->fullscreen_was_positioned = SDL_TRUE;
             SetFullscreen(window, output);
         } else {
-            /* Queue a configure event */
-            struct wl_callback *cb = wl_display_sync(_this->driverdata->display);
-            wl_callback_add_listener(cb, &fullscreen_configure_listener, (void *)((uintptr_t)window->id));
+            ConfigureWindowGeometry(window);
+            CommitLibdecorFrame(window);
         }
     }
 
@@ -2447,6 +2427,8 @@ void Wayland_SetWindowSize(SDL_VideoDevice *_this, SDL_Window *window)
      * Calling this on a custom surface is informative, so the size must
      * always be passed through.
      */
+    FlushFullscreenEvents(window);
+
     if (!(window->flags & (SDL_WINDOW_FULLSCREEN | SDL_WINDOW_MAXIMIZED)) ||
         wind->shell_surface_type == WAYLAND_SURFACE_CUSTOM) {
         wind->requested.width = window->floating.w;