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, 4 insertions, 5 deletions

diff --git a/components/debugger/lib.rs b/components/debugger/lib.rs
index 6190ebec89b..938e16906e3 100644
--- a/components/debugger/lib.rs
+++ b/components/debugger/lib.rs
@@ -4,10 +4,9 @@
 
 #[macro_use]
 extern crate log;
+extern crate servo_channel;
 extern crate ws;
 
-use std::sync::mpsc;
-use std::sync::mpsc::channel;
 use std::thread;
 use ws::{Builder, CloseCode, Handler, Handshake};
 
@@ -15,7 +14,7 @@ enum Message {
     ShutdownServer,
 }
 
-pub struct Sender(mpsc::Sender<Message>);
+pub struct Sender(servo_channel::Sender<Message>);
 
 struct Connection {
     sender: ws::Sender,
@@ -38,7 +37,7 @@ impl Handler for Connection {
 
 pub fn start_server(port: u16) -> Sender {
     debug!("Starting server.");
-    let (sender, receiver) = channel();
+    let (sender, receiver) = servo_channel::channel();
     thread::Builder::new()
         .name("debugger".to_owned())
         .spawn(move || {
@@ -51,7 +50,7 @@ pub fn start_server(port: u16) -> Sender {
                 .spawn(move || {
                     socket.listen(("127.0.0.1", port)).unwrap();
                 }).expect("Thread spawning failed");
-            while let Ok(message) = receiver.recv() {
+            while let Some(message) = receiver.recv() {
                 match message {
                     Message::ShutdownServer => {
                         break;