1 files changed, 7 insertions, 0 deletions
diff --git a/components/script/dom/documentorshadowroot.rs b/components/script/dom/documentorshadowroot.rs
index 577df4bfd51..80b0e0022ba 100644
--- a/components/script/dom/documentorshadowroot.rs
+++ b/components/script/dom/documentorshadowroot.rs
@@ -18,6 +18,7 @@ use script_traits::UntrustedNodeAddress;
 use servo_arc::Arc;
 use std::fmt;
 use style::context::QuirksMode;
+use style::invalidation::media_queries::{MediaListKey, ToMediaListKey};
 use style::media_queries::MediaList;
 use style::shared_lock::{SharedRwLock as StyleSharedRwLock, SharedRwLockReadGuard};
 use style::stylesheet_set::StylesheetSet;
@@ -43,6 +44,12 @@ impl PartialEq for StyleSheetInDocument {
     }
 }
 
+impl ToMediaListKey for StyleSheetInDocument {
+    fn to_media_list_key(&self) -> MediaListKey {
+        self.sheet.to_media_list_key()
+    }
+}
+
 impl ::style::stylesheets::StylesheetInDocument for StyleSheetInDocument {
     fn origin(&self, guard: &SharedRwLockReadGuard) -> Origin {
         self.sheet.origin(guard)