Replace crossbeam with crossbeam-channel

Cargo.toml

@@ -21,7 +21,7 @@ docs = []
 [dependencies]
 async-task = { git = "ssh://git@github.com/async-std/async-task.git" }
 cfg-if = "0.1.9"
-crossbeam = "0.7.1"
+crossbeam-channel = "0.3.9"
 futures-preview = "0.3.0-alpha.17"
 futures-timer = "0.3.0"
 lazy_static = "1.3.0"

src/task/blocking.rs

@@ -4,7 +4,7 @@ use std::fmt;
 use std::pin::Pin;
 use std::thread;
 
-use crossbeam::channel::{unbounded, Receiver, Sender};
+use crossbeam_channel::{unbounded, Receiver, Sender};
 use lazy_static::lazy_static;
 
 use crate::future::Future;

src/task/pool.rs

@@ -6,7 +6,7 @@ use std::pin::Pin;
 use std::ptr;
 use std::thread;
 
-use crossbeam::channel::{unbounded, Sender};
+use crossbeam_channel::{unbounded, Sender};
 use futures::future::FutureExt;
 use lazy_static::lazy_static;