Auto merge of #12501 - mephisto41:worker-close-impl, r=KiChjang

Implement DedicatedWorkerGlobalScope.close

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Implement DedicatedWorkerGlobalScope.close().
---
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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 #12466 (github issue number if applicable).

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- [X] There are tests for these changes

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components/script/dom/dedicatedworkerglobalscope.rs

@@ -370,6 +370,12 @@ impl DedicatedWorkerGlobalScopeMethods for DedicatedWorkerGlobalScope {
         Ok(())
     }
 
+    // https://html.spec.whatwg.org/multipage/#dom-dedicatedworkerglobalscope-close
+    fn Close(&self) {
+        // Step 2
+        self.upcast::<WorkerGlobalScope>().close();
+    }
+
     // https://html.spec.whatwg.org/multipage/#handler-dedicatedworkerglobalscope-onmessage
     event_handler!(message, GetOnmessage, SetOnmessage);
 }