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, 8 deletions

diff --git a/components/devtools_traits/lib.rs b/components/devtools_traits/lib.rs
index dc0979f580c..e0280345169 100644
--- a/components/devtools_traits/lib.rs
+++ b/components/devtools_traits/lib.rs
@@ -13,16 +13,10 @@
 
 #[macro_use]
 extern crate bitflags;
-extern crate http;
-extern crate ipc_channel;
-extern crate malloc_size_of;
 #[macro_use]
 extern crate malloc_size_of_derive;
-extern crate msg;
 #[macro_use]
 extern crate serde;
-extern crate servo_url;
-extern crate time;
 
 use http::method::Method;
 use http::HeaderMap;
@@ -30,8 +24,7 @@ use ipc_channel::ipc::IpcSender;
 use msg::constellation_msg::PipelineId;
 use servo_url::ServoUrl;
 use std::net::TcpStream;
-use time::Duration;
-use time::Tm;
+use time::{self, Duration, Tm};
 
 // Information would be attached to NewGlobal to be received and show in devtools.
 // Extend these fields if we need more information.