Provide a way to set cursor area for IME cursor

Rename `Window::set_ime_position` to `Window::set_ime_cursor_area`
adding a way to create cursor exclusive zone.

Fixes #2886.

src/platform_impl/linux/mod.rs

@@ -512,8 +512,8 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_ime_position(&self, position: Position) {
-        x11_or_wayland!(match self; Window(w) => w.set_ime_position(position))
+    pub fn set_ime_cursor_area(&self, position: Position, size: Size) {
+        x11_or_wayland!(match self; Window(w) => w.set_ime_cursor_area(position, size))
     }
 
     #[inline]

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

@@ -534,12 +534,13 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_ime_position(&self, position: Position) {
+    pub fn set_ime_cursor_area(&self, position: Position, size: Size) {
         let window_state = self.window_state.lock().unwrap();
         if window_state.ime_allowed() {
             let scale_factor = window_state.scale_factor();
             let position = position.to_logical(scale_factor);
-            window_state.set_ime_position(position);
+            let size = size.to_logical(scale_factor);
+            window_state.set_ime_cursor_area(position, size);
         }
     }
 

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

@@ -741,13 +741,14 @@ impl WindowState {
     }
 
     /// Set the IME position.
-    pub fn set_ime_position(&self, position: LogicalPosition<u32>) {
+    pub fn set_ime_cursor_area(&self, position: LogicalPosition<u32>, size: LogicalSize<u32>) {
         // XXX This won't fly unless user will have a way to request IME window per seat, since
         // the ime windows will be overlapping, but winit doesn't expose API to specify for
         // which seat we're setting IME position.
         let (x, y) = (position.x as i32, position.y as i32);
+        let (width, height) = (size.width as i32, size.height as i32);
         for text_input in self.text_inputs.iter() {
-            text_input.set_cursor_rectangle(x, y, 0, 0);
+            text_input.set_cursor_rectangle(x, y, width, height);
             text_input.commit();
         }
     }

src/platform_impl/linux/x11/window.rs

@@ -1510,7 +1510,7 @@ impl UnownedWindow {
     }
 
     #[inline]
-    pub fn set_ime_position(&self, spot: Position) {
+    pub fn set_ime_cursor_area(&self, spot: Position, _size: Size) {
         let (x, y) = spot.to_physical::<i32>(self.scale_factor()).into();
         let _ = self
             .ime_sender