Auto merge of #23017 - emilio:gecko-sync, r=emilio

style: Sync changes from mozilla-central.

See each individual commit for details.

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1 files changed, 20 insertions, 1 deletions

diff --git a/components/style/rule_tree/mod.rs b/components/style/rule_tree/mod.rs
index a2caba6f9f7..f165e1f455f 100644
--- a/components/style/rule_tree/mod.rs
+++ b/components/style/rule_tree/mod.rs
@@ -11,7 +11,7 @@ use crate::applicable_declarations::ApplicableDeclarationList;
 use crate::gecko::selector_parser::PseudoElement;
 use crate::properties::{Importance, LonghandIdSet, PropertyDeclarationBlock};
 use crate::shared_lock::{Locked, SharedRwLockReadGuard, StylesheetGuards};
-use crate::stylesheets::StyleRule;
+use crate::stylesheets::{Origin, StyleRule};
 use crate::thread_state;
 #[cfg(feature = "gecko")]
 use malloc_size_of::{MallocSizeOf, MallocSizeOfOps};
@@ -659,6 +659,25 @@ impl CascadeLevel {
         }
     }
 
+    /// Returns the cascade origin of the rule.
+    #[inline]
+    pub fn origin(&self) -> Origin {
+        match *self {
+            CascadeLevel::UAImportant | CascadeLevel::UANormal => Origin::UserAgent,
+            CascadeLevel::UserImportant | CascadeLevel::UserNormal => Origin::User,
+            CascadeLevel::PresHints |
+            CascadeLevel::InnerShadowNormal |
+            CascadeLevel::SameTreeAuthorNormal |
+            CascadeLevel::StyleAttributeNormal |
+            CascadeLevel::SMILOverride |
+            CascadeLevel::Animations |
+            CascadeLevel::SameTreeAuthorImportant |
+            CascadeLevel::StyleAttributeImportant |
+            CascadeLevel::InnerShadowImportant |
+            CascadeLevel::Transitions => Origin::Author,
+        }
+    }
+
     /// Returns whether this cascade level represents an animation rules.
     #[inline]
     pub fn is_animation(&self) -> bool {