window: Dont take width and height in window constructor

Always set this by scheduling an initial resize.
diff --git a/clients/resizor.c b/clients/resizor.c
index 15900fc..9f9e1b5 100644
--- a/clients/resizor.c
+++ b/clients/resizor.c
@@ -201,7 +201,7 @@
 		return resizor;
 	memset(resizor, 0, sizeof *resizor);
 
-	resizor->window = window_create(display, 500, 400);
+	resizor->window = window_create(display);
 	resizor->widget = frame_create(resizor->window, resizor);
 	window_set_title(resizor->window, "Wayland Resizor");
 	resizor->display = display;