gpui: Refactor PlatformKeyboardLayout (#29653)

Release Notes:

- N/A

crates/gpui/src/platform/mac/platform.rs

@@ -1,5 +1,5 @@
 use super::{
-    BoolExt,
+    BoolExt, MacKeyboardLayout,
     attributed_string::{NSAttributedString, NSMutableAttributedString},
     events::key_to_native,
     is_macos_version_at_least, renderer, screen_capture,
@@ -1579,45 +1579,6 @@ impl UTType {
     }
 }
 
-struct MacKeyboardLayout {
-    id: String,
-    name: String,
-}
-
-impl PlatformKeyboardLayout for MacKeyboardLayout {
-    fn id(&self) -> &str {
-        &self.id
-    }
-
-    fn name(&self) -> &str {
-        &self.name
-    }
-}
-
-impl MacKeyboardLayout {
-    fn new() -> Self {
-        unsafe {
-            let current_keyboard = TISCopyCurrentKeyboardLayoutInputSource();
-
-            let id: *mut Object = TISGetInputSourceProperty(
-                current_keyboard,
-                kTISPropertyInputSourceID as *const c_void,
-            );
-            let id: *const std::os::raw::c_char = msg_send![id, UTF8String];
-            let id = CStr::from_ptr(id).to_str().unwrap().to_string();
-
-            let name: *mut Object = TISGetInputSourceProperty(
-                current_keyboard,
-                kTISPropertyLocalizedName as *const c_void,
-            );
-            let name: *const std::os::raw::c_char = msg_send![name, UTF8String];
-            let name = CStr::from_ptr(name).to_str().unwrap().to_string();
-
-            Self { id, name }
-        }
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use crate::ClipboardItem;