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, 2 deletions

diff --git a/components/script/dom/bindings/conversions.rs b/components/script/dom/bindings/conversions.rs
index a96371aaf06..cf3e45dd770 100644
--- a/components/script/dom/bindings/conversions.rs
+++ b/components/script/dom/bindings/conversions.rs
@@ -40,7 +40,6 @@ use crate::dom::bindings::root::DomRoot;
 use crate::dom::bindings::str::{ByteString, DOMString, USVString};
 use crate::dom::bindings::trace::{JSTraceable, RootedTraceableBox};
 use crate::dom::bindings::utils::DOMClass;
-use js;
 use js::conversions::latin1_to_string;
 pub use js::conversions::ConversionBehavior;
 pub use js::conversions::{ConversionResult, FromJSValConvertible, ToJSValConvertible};
@@ -59,7 +58,6 @@ use js::jsval::{ObjectValue, StringValue, UndefinedValue};
 use js::rust::wrappers::{JS_GetProperty, JS_IsArrayObject};
 use js::rust::{get_object_class, is_dom_class, is_dom_object, maybe_wrap_value, ToString};
 use js::rust::{HandleId, HandleObject, HandleValue, MutableHandleValue};
-use libc;
 use num_traits::Float;
 use servo_config::opts;
 use std::{char, ffi, ptr, slice};