xwayland: Set non zero default saved window size

If a client starts off maximized, clicking the unmaximize button would
result in a 0x0 window - basically a blob of decor with no content.

Instead, use 512x512 as a totally random default value.

Signed-off-by: Derek Foreman <derek.foreman@collabora.com>

xwayland/window-manager.c

@@ -1509,6 +1509,12 @@ weston_wm_window_create(struct weston_wm *wm,
 	window->override_redirect = override;
 	window->width = width;
 	window->height = height;
+	/* Completely arbitrary defaults in case something starts
+	 * maximized and we unmaximize it later - at which point 0 x 0
+	 * would not be the most useful size.
+	 */
+	window->saved_width = 512;
+	window->saved_height = 512;
 	window->x = x;
 	window->y = y;
 	window->pos_dirty = false;