winit-core/window: add Window::request_ime_update

Allow updating IME state atomically to make it easier for platforms
where it's atomic by its nature, like Wayland. The old API is marked
as deprecated and is routed to the new atomic API.

Co-authored-by: dcz <gilapfco.dcz@porcupinefactory.org>

winit-win32/src/window_state.rs

@@ -19,7 +19,7 @@ use windows_sys::Win32::UI::WindowsAndMessaging::{
 use winit_core::icon::Icon;
 use winit_core::keyboard::ModifiersState;
 use winit_core::monitor::Fullscreen;
-use winit_core::window::{Theme, WindowAttributes};
+use winit_core::window::{ImeCapabilities, Theme, WindowAttributes};
 
 use crate::{event_loop, util, SelectedCursor};
 
@@ -48,7 +48,7 @@ pub(crate) struct WindowState {
     pub window_flags: WindowFlags,
 
     pub ime_state: ImeState,
-    pub ime_allowed: bool,
+    pub ime_capabilities: Option<ImeCapabilities>,
 
     // Used by WM_NCACTIVATE, WM_SETFOCUS and WM_KILLFOCUS
     pub is_active: bool,
@@ -178,7 +178,7 @@ impl WindowState {
             window_flags: WindowFlags::empty(),
 
             ime_state: ImeState::Disabled,
-            ime_allowed: false,
+            ime_capabilities: None,
 
             is_active: false,
             is_focused: false,