Auto merge of #22133 - servo:extern-crate, r=SimonSapin

Use 2018-edition idioms in crates that use that edition

The first commit is almost entirely mechanical, created by running `cargo fix --edition-idioms` and relevant crates. I undid the change of adding an anonymous lifetime parameter in types that have implicit lifetimes parameters, for example replacing `&mut Formatter` with `&mut Formatter<'_>`, because I don’t like it. The remaining changes are, in many places:

* Add `dyn` to trait object types, for example `Rc<gl::Gl>` to `Rc<dyn gl::Gl>`. This change also works in the 2015 edition.
* Remove `extern crate` where is it made unneeded by changes to the import/module system.

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1 files changed, 1 insertions, 25 deletions

diff --git a/components/net/tests/main.rs b/components/net/tests/main.rs
index aa7a6aa9cf6..48063adad81 100644
--- a/components/net/tests/main.rs
+++ b/components/net/tests/main.rs
@@ -4,32 +4,8 @@
 
 #![cfg(test)]
 
-extern crate cookie as cookie_rs;
-extern crate devtools_traits;
-extern crate embedder_traits;
-extern crate flate2;
-extern crate futures;
-extern crate headers_core;
-extern crate headers_ext;
-extern crate http;
-extern crate hyper;
-extern crate hyper_serde;
-extern crate ipc_channel;
 #[macro_use]
 extern crate lazy_static;
-extern crate mime;
-extern crate msg;
-extern crate net;
-extern crate net_traits;
-extern crate openssl;
-extern crate profile_traits;
-extern crate servo_channel;
-extern crate servo_config;
-extern crate servo_url;
-extern crate time;
-extern crate tokio;
-extern crate tokio_openssl;
-extern crate url;
 
 mod cookie;
 mod cookie_http_state;
@@ -90,7 +66,7 @@ fn create_embedder_proxy() -> EmbedderProxy {
         }
         impl EventLoopWaker for DummyEventLoopWaker {
             fn wake(&self) {}
-            fn clone(&self) -> Box<EventLoopWaker + Send> {
+            fn clone(&self) -> Box<dyn EventLoopWaker + Send> {
                 Box::new(DummyEventLoopWaker {})
             }
         }