Auto merge of #21111 - gterzian:implement_document_load_cancellation, r=jdm

Implement document load cancellation

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- [ ] `./mach build -d` does not report any errors
- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes fix #19309 fix #21114 fix #21113 (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/script/dom/window.rs

@@ -12,6 +12,7 @@ use dom::bindings::cell::DomRefCell;
 use dom::bindings::codegen::Bindings::DocumentBinding::{DocumentMethods, DocumentReadyState};
 use dom::bindings::codegen::Bindings::FunctionBinding::Function;
 use dom::bindings::codegen::Bindings::HistoryBinding::HistoryBinding::HistoryMethods;
+use dom::bindings::codegen::Bindings::MediaQueryListBinding::MediaQueryListBinding::MediaQueryListMethods;
 use dom::bindings::codegen::Bindings::PermissionStatusBinding::PermissionState;
 use dom::bindings::codegen::Bindings::RequestBinding::RequestInit;
 use dom::bindings::codegen::Bindings::WindowBinding::{self, FrameRequestCallback, WindowMethods};
@@ -27,6 +28,7 @@ use dom::bindings::str::{DOMString, USVString};
 use dom::bindings::structuredclone::StructuredCloneData;
 use dom::bindings::trace::RootedTraceableBox;
 use dom::bindings::utils::{GlobalStaticData, WindowProxyHandler};
+use dom::bindings::weakref::DOMTracker;
 use dom::bluetooth::BluetoothExtraPermissionData;
 use dom::crypto::Crypto;
 use dom::cssstyledeclaration::{CSSModificationAccess, CSSStyleDeclaration, CSSStyleOwner};
@@ -39,7 +41,8 @@ use dom::globalscope::GlobalScope;
 use dom::hashchangeevent::HashChangeEvent;
 use dom::history::History;
 use dom::location::Location;
-use dom::mediaquerylist::{MediaQueryList, WeakMediaQueryListVec};
+use dom::mediaquerylist::{MediaQueryList, MediaQueryListMatchState};
+use dom::mediaquerylistevent::MediaQueryListEvent;
 use dom::messageevent::MessageEvent;
 use dom::navigator::Navigator;
 use dom::node::{Node, NodeDamage, document_from_node, from_untrusted_node_address};
@@ -263,7 +266,7 @@ pub struct Window {
     scroll_offsets: DomRefCell<HashMap<UntrustedNodeAddress, Vector2D<f32>>>,
 
     /// All the MediaQueryLists we need to update
-    media_query_lists: WeakMediaQueryListVec,
+    media_query_lists: DOMTracker<MediaQueryList>,
 
     test_runner: MutNullableDom<TestRunner>,
 
@@ -555,6 +558,13 @@ impl WindowMethods for Window {
         receiver.recv().unwrap();
     }
 
+    // https://html.spec.whatwg.org/multipage/#dom-window-stop
+    fn Stop(&self) {
+        // TODO: Cancel ongoing navigation.
+        let doc = self.Document();
+        doc.abort();
+    }
+
     // https://html.spec.whatwg.org/multipage/#dom-window-closed
     fn Closed(&self) -> bool {
         self.window_proxy.get()
@@ -1048,7 +1058,7 @@ impl WindowMethods for Window {
             media_queries::MediaList::parse(&context, &mut parser);
         let document = self.Document();
         let mql = MediaQueryList::new(&document, media_query_list);
-        self.media_query_lists.push(&*mql);
+        self.media_query_lists.track(&*mql);
         mql
     }
 
@@ -1113,6 +1123,16 @@ impl Window {
         }
     }
 
+    /// Cancels all the tasks from a given task source.
+    /// This sets the current sentinel value to
+    /// `true` and replaces it with a brand new one for future tasks.
+    pub fn cancel_all_tasks_from_source(&self, task_source_name: TaskSourceName) {
+        let mut ignore_flags = self.ignore_further_async_events.borrow_mut();
+        let flag = ignore_flags.entry(task_source_name).or_insert(Default::default());
+        let cancelled = mem::replace(&mut *flag, Default::default());
+        cancelled.store(true, Ordering::Relaxed);
+    }
+
     pub fn clear_js_runtime(&self) {
         // We tear down the active document, which causes all the attached
         // nodes to dispose of their layout data. This messages the layout
@@ -1777,8 +1797,25 @@ impl Window {
         self.parent_info.is_none()
     }
 
+    /// Evaluate media query lists and report changes
+    /// <https://drafts.csswg.org/cssom-view/#evaluate-media-queries-and-report-changes>
     pub fn evaluate_media_queries_and_report_changes(&self) {
-        self.media_query_lists.evaluate_and_report_changes();
+        rooted_vec!(let mut mql_list);
+        self.media_query_lists.for_each(|mql| {
+            if let MediaQueryListMatchState::Changed(_) = mql.evaluate_changes() {
+                // Recording list of changed Media Queries
+                mql_list.push(Dom::from_ref(&*mql));
+            }
+        });
+        // Sending change events for all changed Media Queries
+        for mql in mql_list.iter() {
+            let event = MediaQueryListEvent::new(&mql.global(),
+                                                 atom!("change"),
+                                                 false, false,
+                                                 mql.Media(),
+                                                 mql.Matches());
+            event.upcast::<Event>().fire(mql.upcast::<EventTarget>());
+        }
     }
 
     /// Slow down/speed up timers based on visibility.
@@ -1917,7 +1954,7 @@ impl Window {
             ignore_further_async_events: Default::default(),
             error_reporter,
             scroll_offsets: Default::default(),
-            media_query_lists: WeakMediaQueryListVec::new(),
+            media_query_lists: DOMTracker::new(),
             test_runner: Default::default(),
             webgl_chan,
             webvr_chan,