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/bluetooth/lib.rs b/components/bluetooth/lib.rs
index 8d9f7bd0af5..e563c8fd8a4 100644
--- a/components/bluetooth/lib.rs
+++ b/components/bluetooth/lib.rs
@@ -4,15 +4,8 @@
 
 #[macro_use]
 extern crate bitflags;
-extern crate bluetooth_traits;
-extern crate device;
-extern crate embedder_traits;
-extern crate ipc_channel;
 #[macro_use]
 extern crate log;
-extern crate servo_config;
-extern crate servo_rand;
-extern crate uuid;
 
 pub mod test;
 
@@ -29,7 +22,7 @@ use embedder_traits::{EmbedderMsg, EmbedderProxy};
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
 use servo_config::opts;
 use servo_config::prefs::PREFS;
-use servo_rand::Rng;
+use servo_rand::{self, Rng};
 use std::borrow::ToOwned;
 use std::collections::{HashMap, HashSet};
 use std::string::String;