Auto merge of #13134 - servo:archery, r=emilio

Add lots of Arc’s in style, and prepare for using DOMRefCell

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`DOMRefCell` usage is not there year because of thread-safety questions, but I have this much already that I’d like to land before it bitrots.

r? @emilio

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [x] These changes do not require new tests because refactor

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1 files changed, 0 insertions, 2 deletions

diff --git a/components/script/lib.rs b/components/script/lib.rs
index ff3715de24c..910706f4a1a 100644
--- a/components/script/lib.rs
+++ b/components/script/lib.rs
@@ -17,7 +17,6 @@
 #![feature(slice_patterns)]
 #![feature(stmt_expr_attributes)]
 #![feature(question_mark)]
-#![feature(try_borrow)]
 #![feature(try_from)]
 
 #![deny(unsafe_code)]
@@ -69,7 +68,6 @@ extern crate phf;
 extern crate profile_traits;
 extern crate rand;
 extern crate range;
-extern crate ref_filter_map;
 extern crate ref_slice;
 extern crate regex;
 extern crate rustc_serialize;