Auto merge of #19772 - ferjm:performance.wpt, r=nox

Do not fire pending callbacks on disconnected performance observer

Implement this change in the Performance Timeline API https://github.com/w3c/performance-timeline/issues/66

- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] There are tests for these changes

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components/script/dom/performance.rs

@@ -184,14 +184,6 @@ impl Performance {
             None => return,
         };
 
-        if self.pending_notification_observers_task.get() {
-            if let Some(o) = observers.iter().nth(index) {
-                DOMPerformanceObserver::new(&self.global(),
-                                            o.observer.callback(),
-                                            o.observer.entries()).notify();
-            }
-        }
-
         observers.remove(index);
     }
 

tests/wpt/metadata/performance-timeline/po-disconnect.any.js.ini

@@ -1,11 +0,0 @@
-[po-disconnect.any.html]
-  type: testharness
-  [An observer disconnected after a mark must not have its callback invoked]
-    expected: FAIL
-
-
-[po-disconnect.any.worker.html]
-  type: testharness
-  [An observer disconnected after a mark must not have its callback invoked]
-    expected: FAIL
-