Improve error handling and resource cleanup in linux/x11/window.rs (#21079)

* Fixes registration of event handler for xinput-2 device changes,
revealed by this improvement.

* Pushes `.unwrap()` panic-ing outwards to callers.

* Includes a description of what the X11 call was doing when a failure
was encountered.

* Fixes a variety of places where the X11 reply wasn't being inspected
for failures.

* Destroys windows on failure during setup. New structure makes it
possible for the caller of `open_window` to carry on despite failures,
and so partially initialized window should be removed (though all calls
I looked at also panic currently).

Considered pushing this through `linux/x11/client.rs` too but figured
it'd be nice to minimize merge conflicts with #20853.

Release Notes:

- N/A

crates/gpui/src/platform/linux/x11/client.rs

@@ -776,11 +776,11 @@ impl X11Client {
                     },
                 };
                 let window = self.get_window(event.window)?;
-                window.configure(bounds);
+                window.configure(bounds).unwrap();
             }
             Event::PropertyNotify(event) => {
                 let window = self.get_window(event.window)?;
-                window.property_notify(event);
+                window.property_notify(event).unwrap();
             }
             Event::FocusIn(event) => {
                 let window = self.get_window(event.event)?;
@@ -1258,11 +1258,9 @@ impl LinuxClient for X11Client {
             .iter()
             .enumerate()
             .filter_map(|(root_id, _)| {
-                Some(Rc::new(X11Display::new(
-                    &state.xcb_connection,
-                    state.scale_factor,
-                    root_id,
-                )?) as Rc<dyn PlatformDisplay>)
+                Some(Rc::new(
+                    X11Display::new(&state.xcb_connection, state.scale_factor, root_id).ok()?,
+                ) as Rc<dyn PlatformDisplay>)
             })
             .collect()
     }
@@ -1283,11 +1281,9 @@ impl LinuxClient for X11Client {
     fn display(&self, id: DisplayId) -> Option<Rc<dyn PlatformDisplay>> {
         let state = self.0.borrow();
 
-        Some(Rc::new(X11Display::new(
-            &state.xcb_connection,
-            state.scale_factor,
-            id.0 as usize,
-        )?))
+        Some(Rc::new(
+            X11Display::new(&state.xcb_connection, state.scale_factor, id.0 as usize).ok()?,
+        ))
     }
 
     fn open_window(

crates/gpui/src/platform/linux/x11/display.rs

@@ -13,12 +13,17 @@ pub(crate) struct X11Display {
 
 impl X11Display {
     pub(crate) fn new(
-        xc: &XCBConnection,
+        xcb: &XCBConnection,
         scale_factor: f32,
         x_screen_index: usize,
-    ) -> Option<Self> {
-        let screen = xc.setup().roots.get(x_screen_index).unwrap();
-        Some(Self {
+    ) -> anyhow::Result<Self> {
+        let Some(screen) = xcb.setup().roots.get(x_screen_index) else {
+            return Err(anyhow::anyhow!(
+                "No screen found with index {}",
+                x_screen_index
+            ));
+        };
+        Ok(Self {
             x_screen_index,
             bounds: Bounds {
                 origin: Default::default(),