Auto merge of #26659 - mrobinson:events, r=jdm

Add support for remaining animation and transition events

This PR adds support for remaining animation and transitions events.
There are two commits here. The first is a bit more complicated: it reworks
how rooting is done for animating nodes. Instead of having the `ScriptThread`
try to track which animations are active via events (which can be inaccurate),
it just maintains roots for nodes that are actually present in the animations-
-related data structures. The second commit adds support for the new events.

Unfortunately, the existing events tests either rely on the Web Animations API
or other behavior (for example, that changing animation delay restarts
an animation). Since those two things are out-of-scope for this change,
I've forked some of the WPT tests, removed the reliance on the Web
Animations API, and added them to Servo's internal tests.

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #21564.
- [x] There are tests for these changes OR

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components/script/dom/document.rs

@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 use crate::animation_timeline::AnimationTimeline;
-use crate::animations::{Animations, AnimationsUpdate};
+use crate::animations::Animations;
 use crate::document_loader::{DocumentLoader, LoadType};
 use crate::dom::attr::Attr;
 use crate::dom::beforeunloadevent::BeforeUnloadEvent;
@@ -3750,15 +3750,15 @@ impl Document {
             .collect()
     }
 
-    pub(crate) fn advance_animation_timeline_for_testing(&self, delta: f64) -> AnimationsUpdate {
+    pub(crate) fn advance_animation_timeline_for_testing(&self, delta: f64) {
         self.animation_timeline.borrow_mut().advance_specific(delta);
         let current_timeline_value = self.current_animation_timeline_value();
         self.animations
-            .borrow_mut()
-            .update_for_new_timeline_value(&self.window, current_timeline_value)
+            .borrow()
+            .update_for_new_timeline_value(&self.window, current_timeline_value);
     }
 
-    pub(crate) fn update_animation_timeline(&self) -> AnimationsUpdate {
+    pub(crate) fn update_animation_timeline(&self) {
         // Only update the time if it isn't being managed by a test.
         if !pref!(layout.animations.test.enabled) {
             self.animation_timeline.borrow_mut().update();
@@ -3768,8 +3768,8 @@ impl Document {
         // value might have been advanced previously via the TestBinding.
         let current_timeline_value = self.current_animation_timeline_value();
         self.animations
-            .borrow_mut()
-            .update_for_new_timeline_value(&self.window, current_timeline_value)
+            .borrow()
+            .update_for_new_timeline_value(&self.window, current_timeline_value);
     }
 
     pub(crate) fn current_animation_timeline_value(&self) -> f64 {
@@ -3780,10 +3780,10 @@ impl Document {
         self.animations.borrow()
     }
 
-    pub(crate) fn update_animations_post_reflow(&self) -> AnimationsUpdate {
+    pub(crate) fn update_animations_post_reflow(&self) {
         self.animations
-            .borrow_mut()
-            .do_post_reflow_update(&self.window, self.current_animation_timeline_value())
+            .borrow()
+            .do_post_reflow_update(&self.window, self.current_animation_timeline_value());
     }
 }
 

components/script/dom/window.rs

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-use crate::dom::bindings::cell::DomRefCell;
+use crate::dom::bindings::cell::{DomRefCell, Ref};
 use crate::dom::bindings::codegen::Bindings::DocumentBinding::{
     DocumentMethods, DocumentReadyState,
 };
@@ -410,6 +410,10 @@ impl Window {
         unsafe { JSContext::from_ptr(self.js_runtime.borrow().as_ref().unwrap().cx()) }
     }
 
+    pub fn get_js_runtime(&self) -> Ref<Option<Rc<Runtime>>> {
+        self.js_runtime.borrow()
+    }
+
     pub fn main_thread_script_chan(&self) -> &Sender<MainThreadScriptMsg> {
         &self.script_chan.0
     }
@@ -1581,12 +1585,8 @@ impl Window {
     #[allow(unsafe_code)]
     pub fn advance_animation_clock(&self, delta_ms: i32) {
         let pipeline_id = self.upcast::<GlobalScope>().pipeline_id();
-        let update = self
-            .Document()
+        self.Document()
             .advance_animation_timeline_for_testing(delta_ms as f64 / 1000.);
-        unsafe {
-            ScriptThread::process_animations_update(update);
-        }
         ScriptThread::handle_tick_all_animations_for_testing(pipeline_id);
     }
 
@@ -1752,10 +1752,7 @@ impl Window {
             }
         }
 
-        let update = document.update_animations_post_reflow();
-        unsafe {
-            ScriptThread::process_animations_update(update);
-        }
+        document.update_animations_post_reflow();
 
         true
     }