[macos] Remove Window from EventsLoop's Window list on close and drop

Previously, a Window was only removed from the list when dropped.

src/platform/macos/events_loop.rs

@@ -217,6 +217,18 @@ impl EventsLoop {
         }
     }
 
+    // Removes the window with the given `Id` from the `windows` list.
+    //
+    // This is called when a window is either `Closed` or `Drop`ped.
+    pub fn find_and_remove_window(&self, id: super::window::Id) {
+        if let Ok(mut windows) = self.windows.lock() {
+            windows.retain(|w| match w.upgrade() {
+                Some(w) => w.id() != id,
+                None => true,
+            });
+        }
+    }
+
     fn call_user_callback_with_pending_events(&self) {
         loop {
             let event = match self.pending_events.lock().unwrap().pop_front() {

src/platform/macos/window.rs

@@ -66,6 +66,12 @@ impl WindowDelegate {
                 let state: *mut c_void = *this.get_ivar("winitState");
                 let state = &mut *(state as *mut DelegateState);
                 emit_event(state, WindowEvent::Closed);
+
+                // Remove the window from the events_loop.
+                if let Some(events_loop) = state.events_loop.upgrade() {
+                    let window_id = get_window_id(*state.window);
+                    events_loop.find_and_remove_window(window_id);
+                }
             }
             YES
         }
@@ -173,11 +179,7 @@ impl Drop for Window {
         // Remove this window from the `EventLoop`s list of windows.
         let id = self.id();
         if let Some(ev) = self.delegate.state.events_loop.upgrade() {
-            let mut windows = ev.windows.lock().unwrap();
+            ev.find_and_remove_window(id);
-            windows.retain(|w| match w.upgrade() {
-                Some(w) => w.id() != id,
-                None => true,
-            })
         }
     }
 }