wlr_layer: Update doc-test
//! ```no_run
//! # extern crate wayland_server;
//! #
-//! use smithay::wayland::shell::wlr_layer::{wlr_layer_shell_init, LayerShellRequest};
+//! use smithay::delegate_layer_shell;
+//! use smithay::wayland::shell::wlr_layer::{WlrLayerShellState, WlrLayerShellHandler, LayerShellRequest};
//!
-//! # let mut display = wayland_server::Display::new();
-//! let (shell_state, _) = wlr_layer_shell_init(
-//! &mut display,
-//! // your implementation
-//! |event: LayerShellRequest, dispatch_data| { /* handle the shell requests here */ },
+//! # struct State { layer_shell_state: WlrLayerShellState }
+//! # let mut display = wayland_server::Display::<State>::new().unwrap();
+//! let layer_shell_state = WlrLayerShellState::new::<State, _>(
+//! &display.handle(),
//! None // put a logger if you want
//! );
//!
+//! // - Put your layer_shell_state into your `State`.
+//! // - And implement `LayerShellHandler
+//! impl WlrLayerShellHandler for State {
+//! fn shell_state(&mut self) -> &mut WlrLayerShellState {
+//! &mut self.layer_shell_state
+//! }
+//! fn request(&mut self, dh: &wayland_server::DisplayHandle, request: LayerShellRequest) {
+//! # let _ = (dh, request);
+//! // your implementation
+//! }
+//! }
+//! // let smithay implement wayland_server::DelegateDispatch
+//! delegate_layer_shell!(State);
+//!
//! // You're now ready to go!
//! ```
