chore(tests): fix tests when tokio-proto feature disabled

src/mock.rs

@@ -87,9 +87,6 @@ impl<T> AsyncIo<T> {
 }
 
 impl AsyncIo<Buf> {
-    #[cfg(feature = "tokio-proto")]
-    //TODO: fix proto::conn::tests to not use tokio-proto API,
-    //and then this cfg flag go away
     pub fn new_buf<T: Into<Vec<u8>>>(buf: T, bytes: usize) -> AsyncIo<Buf> {
         AsyncIo::new(Buf::wrap(buf.into()), bytes)
     }