Properly implement Debug for Window and EventLoop types (#3297)

For EventLoop, EventLoopBuilder, EventLoopProxy and by requiring it as
a supertrait of Window and ActiveEventLoop.

It is especially useful for user to be able to know that Window is Debug.

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

@@ -45,6 +45,7 @@ pub(crate) enum Event {
 }
 
 /// The Wayland event loop.
+#[derive(Debug)]
 pub struct EventLoop {
     /// Has `run` or `run_on_demand` been called or a call to `pump_events` that starts the loop
     loop_running: bool,
@@ -546,6 +547,7 @@ impl AsRawFd for EventLoop {
     }
 }
 
+#[derive(Debug)]
 pub struct ActiveEventLoop {
     /// Event loop proxy
     event_loop_proxy: CoreEventLoopProxy,
@@ -665,6 +667,7 @@ impl rwh_06::HasDisplayHandle for ActiveEventLoop {
     }
 }
 
+#[derive(Debug)]
 pub struct OwnedDisplayHandle {
     pub(crate) connection: Connection,
 }

src/platform_impl/linux/wayland/event_loop/proxy.rs

@@ -7,6 +7,7 @@ use sctk::reexports::calloop::ping::Ping;
 use crate::event_loop::{EventLoopProxy as CoreEventLoopProxy, EventLoopProxyProvider};
 
 /// A handle that can be sent across the threads and used to wake up the `EventLoop`.
+#[derive(Debug)]
 pub struct EventLoopProxy {
     ping: Ping,
 }

src/platform_impl/linux/wayland/event_loop/sink.rs

@@ -8,7 +8,7 @@ use crate::window::WindowId;
 
 /// An event loop's sink to deliver events from the Wayland event callbacks
 /// to the winit's user.
-#[derive(Default)]
+#[derive(Default, Debug)]
 pub struct EventSink {
     pub(crate) window_events: Vec<Event>,
 }

src/platform_impl/linux/wayland/seat/pointer/mod.rs

@@ -414,6 +414,7 @@ impl WinitPointerDataExt for WlPointer {
     }
 }
 
+#[derive(Debug)]
 pub struct PointerConstraintsState {
     pointer_constraints: ZwpPointerConstraintsV1,
 }

src/platform_impl/linux/wayland/seat/pointer/relative_pointer.rs

@@ -16,6 +16,7 @@ use crate::event::DeviceEvent;
 use crate::platform_impl::wayland::state::WinitState;
 
 /// Wrapper around the relative pointer.
+#[derive(Debug)]
 pub struct RelativePointerState {
     manager: ZwpRelativePointerManagerV1,
 }

src/platform_impl/linux/wayland/seat/text_input/mod.rs

@@ -14,6 +14,7 @@ use crate::platform_impl::wayland;
 use crate::platform_impl::wayland::state::WinitState;
 use crate::window::ImePurpose;
 
+#[derive(Debug)]
 pub struct TextInputState {
     text_input_manager: ZwpTextInputManagerV3,
 }

src/platform_impl/linux/wayland/state.rs

@@ -36,6 +36,7 @@ use crate::platform_impl::wayland::window::{WindowRequests, WindowState};
 use crate::platform_impl::wayland::WindowId;
 
 /// Winit's Wayland state.
+#[derive(Debug)]
 pub struct WinitState {
     /// The WlRegistry.
     pub registry_state: RegistryState,

src/platform_impl/linux/wayland/types/xdg_activation.rs

@@ -16,6 +16,7 @@ use crate::event_loop::AsyncRequestSerial;
 use crate::platform_impl::wayland::state::WinitState;
 use crate::window::{ActivationToken, WindowId};
 
+#[derive(Debug)]
 pub struct XdgActivationState {
     xdg_activation: XdgActivationV1,
 }

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

@@ -34,6 +34,7 @@ pub(crate) mod state;
 pub use state::WindowState;
 
 /// The Wayland window.
+#[derive(Debug)]
 pub struct Window {
     /// Reference to the underlying SCTK window.
     window: SctkWindow,

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

@@ -51,6 +51,7 @@ pub type WinitFrame = sctk::shell::xdg::fallback_frame::FallbackFrame<WinitState
 const MIN_WINDOW_SIZE: LogicalSize<u32> = LogicalSize::new(2, 1);
 
 /// The state of the window which is being updated from the [`WinitState`].
+#[derive(Debug)]
 pub struct WindowState {
     /// The connection to Wayland server.
     pub handle: Arc<OwnedDisplayHandle>,
@@ -1097,7 +1098,7 @@ impl Drop for WindowState {
 }
 
 /// The state of the cursor grabs.
-#[derive(Clone, Copy)]
+#[derive(Clone, Copy, Debug)]
 struct GrabState {
     /// The grab mode requested by the user.
     user_grab_mode: CursorGrabMode,