Have EventLoopClosed contain the original event (#1294)

* Fix issue #1292

* Remove "optionally" from changelog entry

src/platform_impl/linux/wayland/event_loop.rs

@@ -282,8 +282,14 @@ impl<T: 'static> Clone for EventLoopProxy<T> {
 }
 
 impl<T: 'static> EventLoopProxy<T> {
-    pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed> {
-        self.user_sender.send(event).map_err(|_| EventLoopClosed)
+    pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed<T>> {
+        self.user_sender.send(event).map_err(|e| {
+            EventLoopClosed(if let ::calloop::channel::SendError::Disconnected(x) = e {
+                x
+            } else {
+                unreachable!()
+            })
+        })
     }
 }