Auto merge of #16702 - bholley:custom_arc, r=emilio

Use a custom arc in the style system

See https://bugzilla.mozilla.org/show_bug.cgi?id=1360889

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1 files changed, 7 insertions, 0 deletions

diff --git a/components/script/dom/bindings/trace.rs b/components/script/dom/bindings/trace.rs
index 1bc9c165fb1..2ecae0d9d73 100644
--- a/components/script/dom/bindings/trace.rs
+++ b/components/script/dom/bindings/trace.rs
@@ -99,6 +99,7 @@ use style::media_queries::MediaList;
 use style::properties::PropertyDeclarationBlock;
 use style::selector_parser::{PseudoElement, Snapshot};
 use style::shared_lock::{SharedRwLock as StyleSharedRwLock, Locked as StyleLocked};
+use style::stylearc::Arc as StyleArc;
 use style::stylesheets::{CssRules, FontFaceRule, KeyframesRule, MediaRule};
 use style::stylesheets::{NamespaceRule, StyleRule, ImportRule, SupportsRule};
 use style::values::specified::Length;
@@ -166,6 +167,12 @@ unsafe impl<T: JSTraceable> JSTraceable for Arc<T> {
     }
 }
 
+unsafe impl<T: JSTraceable> JSTraceable for StyleArc<T> {
+    unsafe fn trace(&self, trc: *mut JSTracer) {
+        (**self).trace(trc)
+    }
+}
+
 unsafe impl<T: JSTraceable + ?Sized> JSTraceable for Box<T> {
     unsafe fn trace(&self, trc: *mut JSTracer) {
         (**self).trace(trc)