Auto merge of #21325 - gterzian:crossbeam_integration, r=SimonSapin,jdm

Replace mpsc with crossbeam-channel

Follow up on https://github.com/servo/servo/pull/19515

---

Selecting over multiple channels in `std::sync::mpsc` is not stable and likely never will be:

https://github.com/rust-lang/rust/issues/27800#issuecomment-260136777
> It seems the only thing keeping `mpsc_select` around is Servo.

crossbeam-channel is designed specifically to replace `std::sync::mpsc` and fix many of its shortcomings:
https://github.com/stjepang/rfcs-crossbeam/blob/channel/text/2017-11-09-channel.md

This is to be landed together with https://github.com/servo/ipc-channel/pull/183.

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1 files changed, 3 insertions, 2 deletions

diff --git a/components/devtools/lib.rs b/components/devtools/lib.rs
index 2e11fa0eda2..8bd34c0a1d0 100644
--- a/components/devtools/lib.rs
+++ b/components/devtools/lib.rs
@@ -21,6 +21,7 @@ extern crate msg;
 #[macro_use]
 extern crate serde;
 extern crate serde_json;
+extern crate servo_channel;
 extern crate time;
 
 use actor::{Actor, ActorRegistry};
@@ -41,13 +42,13 @@ use devtools_traits::{ScriptToDevtoolsControlMsg, WorkerId};
 use ipc_channel::ipc::IpcSender;
 use msg::constellation_msg::PipelineId;
 use protocol::JsonPacketStream;
+use servo_channel::{Receiver, Sender, channel};
 use std::borrow::ToOwned;
 use std::cell::RefCell;
 use std::collections::HashMap;
 use std::collections::hash_map::Entry::{Occupied, Vacant};
 use std::net::{Shutdown, TcpListener, TcpStream};
 use std::sync::{Arc, Mutex};
-use std::sync::mpsc::{Receiver, Sender, channel};
 use std::thread;
 use time::precise_time_ns;
 
@@ -509,7 +510,7 @@ fn run_server(
             }
         }).expect("Thread spawning failed");
 
-    while let Ok(msg) = receiver.recv() {
+    while let Some(msg) = receiver.recv() {
         match msg {
             DevtoolsControlMsg::FromChrome(ChromeToDevtoolsControlMsg::AddClient(stream)) => {
                 let actors = actors.clone();