make suppressed and aggregate errors to be serializable

IndexedDB/structured-clone.any.js

@@ -227,6 +227,23 @@ cloneObjectTest(new Set([1,2,3,4]), (orig, clone) => {
   assert_equals(orig.message, clone.message);
 }));
 
+[
+  new SuppressedError(),
+  new SuppressedError(new Error('resulted'), new Error('suppressed')),
+].forEach(value => cloneObjectTest(value, (orig, clone) => {
+  assert_equals(orig.name, clone.name);
+  assert_equals(orig.error.message, clone.error.message);
+  assert_equals(orig.suppressed.message, clone.suppressed.message);
+}));
+
+[
+  new AggregateError([]),
+  new AggregateError([new Error('hello')], 'abc'),
+].forEach(value => cloneObjectTest(value, (orig, clone) => {
+  assert_equals(orig.name, clone.name);
+  assert_equals(orig.errors[0].message, clone.errors[0].message);
+}));
+
 // Arrays
 [
   [],

html/browsers/the-window-object/window-properties.https.html

@@ -238,7 +238,7 @@
   // 15.1.4 Constructor Properties of the Global Object
   ["Object", "Function", "Array", "String", "Boolean", "Number", "Date",
    "RegExp", "Error", "EvalError", "RangeError", "ReferenceError",
-   "SyntaxError", "TypeError", "URIError"].forEach(function(id) {
+   "SyntaxError", "TypeError", "URIError", "AggregateError", "SuppressedError"].forEach(function(id) {
     test(function() {
       assert_true(id in window, id + " in window");
       assert_data_propdesc(Object.getOwnPropertyDescriptor(window, id),

html/infrastructure/safe-passing-of-structured-data/structuredclone_0.html

@@ -605,6 +605,39 @@
                     assert_unreached("Window must not be clonable");
                 });
             },
+            function() {
+                var t = async_test("SuppressedError objects can be cloned");
+                t.id = 41;
+                worker.onmessage = t.step_func_done(function(e) {
+                    assert_equals(Object.getPrototypeOf(e.data), SuppressedError.prototype, "Checking prototype");
+                    assert_equals(e.data.constructor, SuppressedError, "Checking constructor");
+                    assert_equals(e.data.name, "SuppressedError", "Checking name");
+                    assert_equals(e.data.error.message, "resulted", "Checking resulted error message");
+                    assert_equals(e.data.suppressed.message, "suppressed", "Checking suppressed error message");
+                    assert_equals(e.data.foo, undefined, "Checking custom property");
+                });
+                t.step(function() {
+                    const error = SuppressedError(new Error('resulted'), new Error('suppressed'));
+                    error.foo = "bar";
+                    worker.postMessage(error);
+                });
+            },
+            function() {
+                var t = async_test("AggregateError objects can be cloned");
+                t.id = 42;
+                worker.onmessage = t.step_func_done(function(e) {
+                    assert_equals(Object.getPrototypeOf(e.data), AggregateErro.[prototype, "Checking prototype");
+                    assert_equals(e.data.constructor, AggregateError, "Checking constructor");
+                    assert_equals(e.data.name, "AggregateError", "Checking name");
+                    assert_equals(e.data.errors[0].message, "some message", "Checking message");
+                    assert_equals(e.data.foo, undefined, "Checking custom property");
+                });
+                t.step(function() {
+                    const error = AggregateError([new Error('some message')]);
+                    error.foo = "bar";
+                    worker.postMessage(error);
+                });
+            },
         ];
     }, {explicit_done:true});