Auto merge of #14592 - asajeffrey:util-goodbye, r=mbrubeck

Remove the util crate

<!-- Please describe your changes on the following line: -->

This PR removes the `util` crate.

* Replaced the `spawn_named` and `clamp` functions by appropriate uses of `std::thread::Builder::spawn`, `std::cmp::min` and `std::cmp::max`.
* Moved `opts`, `prefs` and `resource_files` into a new `config` crate.
* Moved `remutex` and `geometry` into their own crates.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because they are refactorings

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/14592)
<!-- Reviewable:end -->

1 files changed, 5 insertions, 6 deletions

diff --git a/components/debugger/lib.rs b/components/debugger/lib.rs
index 25983561d5d..25b3c4890a6 100644
--- a/components/debugger/lib.rs
+++ b/components/debugger/lib.rs
@@ -4,13 +4,12 @@
 
 #[macro_use]
 extern crate log;
-extern crate util;
 #[cfg(not(target_os = "android"))]
 extern crate ws;
 
 use std::sync::mpsc;
 use std::sync::mpsc::channel;
-use util::thread::spawn_named;
+use std::thread;
 #[cfg(not(target_os = "android"))]
 use ws::{Builder, CloseCode, Handler, Handshake};
 
@@ -45,14 +44,14 @@ impl Handler for Connection {
 pub fn start_server(port: u16) -> Sender {
     debug!("Starting server.");
     let (sender, receiver) = channel();
-    spawn_named("debugger".to_owned(), move || {
+    thread::Builder::new().name("debugger".to_owned()).spawn(move || {
         let socket = Builder::new().build(|sender: ws::Sender| {
             Connection { sender: sender }
         }).unwrap();
         let sender = socket.broadcaster();
-        spawn_named("debugger-websocket".to_owned(), move || {
+        thread::Builder::new().name("debugger-websocket".to_owned()).spawn(move || {
             socket.listen(("127.0.0.1", port)).unwrap();
-        });
+        }).expect("Thread spawning failed");
         while let Ok(message) = receiver.recv() {
             match message {
                 Message::ShutdownServer => {
@@ -61,7 +60,7 @@ pub fn start_server(port: u16) -> Sender {
             }
         }
         sender.shutdown().unwrap();
-    });
+    }).expect("Thread spawning failed");
     Sender(sender)
 }