Implement BroadcastChannel

third_party/WebKit/Source/modules/broadcastchannel/BroadcastChannel.idl

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// https://html.spec.whatwg.org/multipage/comms.html#broadcastchannel
+
+[
+    Constructor(DOMString name),
+    ConstructorCallWith=ExecutionContext,
+    RuntimeEnabled=BroadcastChannel,
+    Exposed=(Window,Worker),
+    ActiveScriptWrappable,
+    DependentLifetime,
+] interface BroadcastChannel : EventTarget {
+    readonly attribute DOMString name;
+
+    [RaisesException] void postMessage(any message);
+    void close();
+
+    // event handlers
+    attribute EventHandler onmessage;
+};