Unify behavior of resizable across platforms

This makes X11 and Wayland follow Windows and macOS, so the size of the
window could be set even though it has resizable attribute set to false.

Fixes #2242.

src/platform_impl/linux/wayland/window/mod.rs

@@ -220,6 +220,9 @@ impl Window {
             window_requests.clone(),
         );
 
+        // Set resizable state, so we can determine how to handle `Window::set_inner_size`.
+        window_handle.is_resizable.set(attributes.resizable);
+
         let mut winit_state = event_loop_window_target.state.borrow_mut();
 
         winit_state.window_map.insert(window_id, window_handle);