Auto merge of #23325 - emilio:gecko-sync, r=emilio

style: Sync changes from mozilla-central.

See each individual commit for details.

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1 files changed, 8 insertions, 1 deletions

diff --git a/components/style/stylesheet_set.rs b/components/style/stylesheet_set.rs
index d2c3ad0f88e..d8c21d5494c 100644
--- a/components/style/stylesheet_set.rs
+++ b/components/style/stylesheet_set.rs
@@ -468,7 +468,14 @@ where
             .fold(0, |s, (item, _)| s + item.len())
     }
 
+    /// Returns the count of stylesheets for a given origin.
+    #[inline]
+    pub fn sheet_count(&self, origin: Origin) -> usize {
+        self.collections.borrow_for_origin(&origin).len()
+    }
+
     /// Returns the `index`th stylesheet in the set for the given origin.
+    #[inline]
     pub fn get(&self, origin: Origin, index: usize) -> Option<&S> {
         self.collections.borrow_for_origin(&origin).get(index)
     }
@@ -539,7 +546,7 @@ where
     }
 }
 
-/// The set of stylesheets effective for a given XBL binding or Shadow Root.
+/// The set of stylesheets effective for a given Shadow Root.
 #[derive(MallocSizeOf)]
 pub struct AuthorStylesheetSet<S>
 where