linux: Get the color scheme through xdg-desktop-portal (#11926)

The method has been tested on:
- Gnome 46 (Working)
- Gnome 40 (Not supported)

Tasks

- [x] Implements a draft which get and provides the user theme to
components which needs it
- [x] Implements a way to call the callback function when the theme is
updated
- [X] Cleans the code

Release notes:
- N/A

crates/gpui/src/platform/linux/platform.rs

@@ -8,6 +8,7 @@ use std::io::Read;
 use std::ops::{Deref, DerefMut};
 use std::os::fd::{AsRawFd, FromRawFd};
 use std::panic::Location;
+use std::rc::Weak;
 use std::{
     path::{Path, PathBuf},
     process::Command,
@@ -27,11 +28,13 @@ use flume::{Receiver, Sender};
 use futures::channel::oneshot;
 use parking_lot::Mutex;
 use time::UtcOffset;
+use util::ResultExt;
 use wayland_client::Connection;
 use wayland_protocols::wp::cursor_shape::v1::client::wp_cursor_shape_device_v1::Shape;
 use xkbcommon::xkb::{self, Keycode, Keysym, State};
 
 use crate::platform::linux::wayland::WaylandClient;
+use crate::platform::linux::xdg_desktop_portal::window_appearance;
 use crate::{
     px, Action, AnyWindowHandle, BackgroundExecutor, ClipboardItem, CosmicTextSystem, CursorStyle,
     DisplayId, ForegroundExecutor, Keymap, Keystroke, LinuxDispatcher, Menu, MenuItem, Modifiers,
@@ -86,6 +89,7 @@ pub(crate) struct LinuxCommon {
     pub(crate) background_executor: BackgroundExecutor,
     pub(crate) foreground_executor: ForegroundExecutor,
     pub(crate) text_system: Arc<CosmicTextSystem>,
+    pub(crate) appearance: WindowAppearance,
     pub(crate) callbacks: PlatformHandlers,
     pub(crate) signal: LoopSignal,
 }
@@ -96,12 +100,18 @@ impl LinuxCommon {
         let text_system = Arc::new(CosmicTextSystem::new());
         let callbacks = PlatformHandlers::default();
 
-        let dispatcher = Arc::new(LinuxDispatcher::new(main_sender));
+        let dispatcher = Arc::new(LinuxDispatcher::new(main_sender.clone()));
+
+        let background_executor = BackgroundExecutor::new(dispatcher.clone());
+        let appearance = window_appearance(&background_executor)
+            .log_err()
+            .unwrap_or(WindowAppearance::Light);
 
         let common = LinuxCommon {
-            background_executor: BackgroundExecutor::new(dispatcher.clone()),
+            background_executor,
             foreground_executor: ForegroundExecutor::new(dispatcher.clone()),
             text_system,
+            appearance,
             callbacks,
             signal,
         };
@@ -462,8 +472,8 @@ impl<P: LinuxClient + 'static> Platform for P {
         })
     }
 
-    fn window_appearance(&self) -> crate::WindowAppearance {
-        crate::WindowAppearance::Light
+    fn window_appearance(&self) -> WindowAppearance {
+        self.with_common(|common| common.appearance)
     }
 
     fn register_url_scheme(&self, _: &str) -> Task<anyhow::Result<()>> {