Auto merge of #17701 - bholley:reuse_allocations, r=emilio

reuse the bloom filter and style sharing cache across traversals

https://bugzilla.mozilla.org/show_bug.cgi?id=1380198

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1 files changed, 6 insertions, 1 deletions

diff --git a/components/servo_arc/lib.rs b/components/servo_arc/lib.rs
index 0040fdea6d1..ff4074767f8 100644
--- a/components/servo_arc/lib.rs
+++ b/components/servo_arc/lib.rs
@@ -22,14 +22,16 @@
 // duplicate those here.
 #![allow(missing_docs)]
 
-#[cfg(feature = "servo")] extern crate serde;
 extern crate nodrop;
+#[cfg(feature = "servo")] extern crate serde;
+extern crate stable_deref_trait;
 
 #[cfg(feature = "servo")]
 use heapsize::HeapSizeOf;
 use nodrop::NoDrop;
 #[cfg(feature = "servo")]
 use serde::{Deserialize, Serialize};
+use stable_deref_trait::{CloneStableDeref, StableDeref};
 use std::{isize, usize};
 use std::borrow;
 use std::cmp::Ordering;
@@ -432,6 +434,9 @@ impl<T: ?Sized> AsRef<T> for Arc<T> {
     }
 }
 
+unsafe impl<T: ?Sized> StableDeref for Arc<T> {}
+unsafe impl<T: ?Sized> CloneStableDeref for Arc<T> {}
+
 // This is what the HeapSize crate does for regular arc, but is questionably
 // sound. See https://github.com/servo/heapsize/issues/37
 #[cfg(feature = "servo")]