Fix building with the event-stream feature (#566)

src/event/source/unix.rs

@@ -151,8 +151,7 @@ impl EventSource for UnixInternalEventSource {
                         return Err(std::io::Error::new(
                             std::io::ErrorKind::Interrupted,
                             "Poll operation was woken up by `Waker::wake`",
-                        )
-                        .into());
+                        ));
                     }
                     _ => unreachable!("Synchronize Evented handle registration & token handling"),
                 }

src/event/sys/unix/waker.rs

@@ -2,7 +2,7 @@ use std::sync::{Arc, Mutex};
 
 use mio::{Registry, Token};
 
-use crate::{ErrorKind, Result};
+use crate::Result;
 
 /// Allows to wake up the `mio::Poll::poll()` method.
 /// This type wraps `mio::Waker`, for more information see its documentation.
@@ -23,11 +23,7 @@ impl Waker {
     ///
     /// Readiness is set to `Ready::readable()`.
     pub(crate) fn wake(&self) -> Result<()> {
-        self.inner
-            .lock()
-            .unwrap()
-            .wake()
-            .map_err(ErrorKind::IoError)
+        self.inner.lock().unwrap().wake()
     }
 
     /// Resets the state so the same waker can be reused.