Update the secure-contexts IDL file and test (web-platform-tests#9848)

interfaces/secure-contexts.idl

@@ -0,0 +1,8 @@
+// GENERATED CONTENT - DO NOT EDIT
+// Content of this file was automatically extracted from the
+// "Secure Contexts" spec.
+// See: https://w3c.github.io/webappsec-secure-contexts/
+
+partial interface WindowOrWorkerGlobalScope {
+  readonly attribute boolean isSecureContext;
+};

secure-contexts/idlharness.any.js

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+// META: global=window,worker
+// META: script=/resources/WebIDLParser.js
+// META: script=/resources/idlharness.js
+
+// https://w3c.github.io/webappsec-secure-contexts/
+
+'use strict';
+
+promise_test(async () => {
+  const idl = await fetch("/interfaces/secure-contexts.idl").then(r => r.text());
+  const workers = await fetch("/interfaces/dedicated-workers.idl").then(r => r.text());
+
+  const idl_array = new IdlArray();
+  idl_array.add_idls(idl);
+  idl_array.add_dependency_idls(workers);
+  idl_array.add_objects({
+    WindowOrWorkerGlobalScope: ["self"],
+  });
+  idl_array.test();
+}, "Test IDL implementation of Secure Contexts");