wayland: Early-out sooner when requesting fullscreen on a popup

Exit the fullscreen sequence sooner if it is requested that a popup window be fullscreen.

The surface commit formerly in this path is irrelevant and can be removed as previous changes made it so that SetFullscreen() is no longer called from anywhere except Wayland_SetWindowFullscreen().

src/video/wayland/SDL_waylandwindow.c

@@ -392,13 +392,6 @@ SetFullscreen(SDL_Window *window, struct wl_output *output)
     SDL_WindowData *wind = window->driverdata;
     SDL_VideoData *viddata = wind->waylandData;
 
-    /* Pop-ups don't get to be fullscreened */
-    if (wind->shell_surface_type == WAYLAND_SURFACE_XDG_POPUP) {
-        /* ... but we still want to commit, particularly for ShowWindow */
-        wl_surface_commit(wind->surface);
-        return;
-    }
-
     /* The desktop may try to enforce min/max sizes here, so turn them off for
      * fullscreen and on (if applicable) for windowed
      */
@@ -1732,8 +1725,8 @@ Wayland_SetWindowFullscreen(_THIS, SDL_Window * window,
     struct wl_output *output = ((SDL_WaylandOutputData*) _display->driverdata)->output;
     SDL_VideoData *viddata = (SDL_VideoData *) _this->driverdata;
 
-    /* Called from within a configure event, drop it. */
-    if (wind->in_fullscreen_transition) {
+    /* Called from within a configure event or the window is a popup, drop it. */
+    if (wind->in_fullscreen_transition || wind->shell_surface_type == WAYLAND_SURFACE_XDG_POPUP) {
         return;
     }