Auto merge of #18037 - heycam:split-cascade-font-counter, r=emilio

style: Split collected @font-face / @counter-style rules per origin.

<!-- Please describe your changes on the following line: -->

More refactoring in preparation for rebuilding sheets only from the origin that changed.

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- [ ] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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components/style/gecko/data.rs

@@ -4,10 +4,8 @@
 
 //! Data needed to style a Gecko document.
 
-use Atom;
 use atomic_refcell::{AtomicRef, AtomicRefCell, AtomicRefMut};
 use dom::TElement;
-use gecko::rules::{CounterStyleRule, FontFaceRule};
 use gecko_bindings::bindings::{self, RawServoStyleSet};
 use gecko_bindings::structs::{ServoStyleSheet, StyleSheetInfo, ServoStyleSheetInner};
 use gecko_bindings::structs::RawGeckoPresContextOwned;
@@ -16,11 +14,10 @@ use gecko_bindings::sugar::ownership::{HasArcFFI, HasBoxFFI, HasFFI, HasSimpleFF
 use invalidation::media_queries::{MediaListKey, ToMediaListKey};
 use media_queries::{Device, MediaList};
 use properties::ComputedValues;
-use selector_map::PrecomputedHashMap;
 use servo_arc::Arc;
 use shared_lock::{Locked, StylesheetGuards, SharedRwLockReadGuard};
 use stylesheet_set::StylesheetSet;
-use stylesheets::{Origin, StylesheetContents, StylesheetInDocument};
+use stylesheets::{StylesheetContents, StylesheetInDocument};
 use stylist::{ExtraStyleData, Stylist};
 
 /// Little wrapper to a Gecko style sheet.
@@ -120,11 +117,8 @@ pub struct PerDocumentStyleDataImpl {
     /// List of stylesheets, mirrored from Gecko.
     pub stylesheets: StylesheetSet<GeckoStyleSheet>,
 
-    /// List of effective font face rules.
-    pub font_faces: Vec<(Arc<Locked<FontFaceRule>>, Origin)>,
-
-    /// Map for effective counter style rules.
-    pub counter_styles: PrecomputedHashMap<Atom, Arc<Locked<CounterStyleRule>>>,
+    /// List of effective @font-face and @counter-style rules.
+    pub extra_style_data: ExtraStyleData,
 }
 
 /// The data itself is an `AtomicRefCell`, which guarantees the proper semantics
@@ -142,8 +136,7 @@ impl PerDocumentStyleData {
         PerDocumentStyleData(AtomicRefCell::new(PerDocumentStyleDataImpl {
             stylist: Stylist::new(device, quirks_mode.into()),
             stylesheets: StylesheetSet::new(),
-            font_faces: vec![],
-            counter_styles: PrecomputedHashMap::default(),
+            extra_style_data: Default::default(),
         }))
     }
 
@@ -169,11 +162,6 @@ impl PerDocumentStyleDataImpl {
             return;
         }
 
-        let mut extra_data = ExtraStyleData {
-            font_faces: &mut self.font_faces,
-            counter_styles: &mut self.counter_styles,
-        };
-
         let author_style_disabled = self.stylesheets.author_style_disabled();
         self.stylist.clear();
         let iter = self.stylesheets.flush(document_element);
@@ -183,7 +171,7 @@ impl PerDocumentStyleDataImpl {
             /* ua_sheets = */ None,
             /* stylesheets_changed = */ true,
             author_style_disabled,
-            &mut extra_data
+            &mut self.extra_style_data,
         );
     }