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, 0 insertions, 33 deletions

diff --git a/components/layout/lib.rs b/components/layout/lib.rs
index b91ee22eba8..2bf13e32173 100644
--- a/components/layout/lib.rs
+++ b/components/layout/lib.rs
@@ -4,49 +4,16 @@
 
 #![deny(unsafe_code)]
 
-extern crate app_units;
-extern crate atomic_refcell;
 #[macro_use]
 extern crate bitflags;
-extern crate canvas_traits;
-extern crate euclid;
-extern crate fnv;
-extern crate fxhash;
-extern crate gfx;
-extern crate gfx_traits;
 #[macro_use]
 extern crate html5ever;
-extern crate ipc_channel;
-extern crate libc;
 #[macro_use]
 extern crate log;
-extern crate malloc_size_of;
-extern crate msg;
-extern crate net_traits;
-extern crate ordered_float;
-extern crate parking_lot;
-extern crate profile_traits;
 #[macro_use]
 extern crate range;
-extern crate rayon;
-extern crate script_layout_interface;
-extern crate script_traits;
 #[macro_use]
 extern crate serde;
-extern crate serde_json;
-extern crate servo_arc;
-extern crate servo_atoms;
-extern crate servo_channel;
-extern crate servo_config;
-extern crate servo_geometry;
-extern crate servo_url;
-extern crate smallvec;
-extern crate style;
-extern crate style_traits;
-extern crate unicode_bidi;
-extern crate unicode_script;
-extern crate webrender_api;
-extern crate xi_unicode;
 
 #[macro_use]
 pub mod layout_debug;