Allow a main interstitial frame to act as an ExtensionMessagePort opener

chrome/test/data/extensions/api_test/messaging/interstitial_component/contentscript.js

+// 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.
+
+var testPort = chrome.runtime.connect({
+  name: 'port from interstitial'
+});
+
+var currentTest;
+testPort.onMessage.addListener(function(msg) {
+  console.assert(!currentTest, 'Should only run one test at a time');
+  currentTest = msg;
+
+  if (msg === 'testSendMessage') {
+    testSendMessage();
+  } else if (msg === 'testDisconnectByBackground') {
+    testDisconnectByBackground();
+  } else if (msg === 'testDisconnectByInterstitial') {
+    testDisconnectByInterstitial();
+  } else {
+    done('Unexpected test: ' + msg);
+  }
+});
+
+function done(test) {
+  console.assert(test === currentTest, 'test name should match current test');
+  currentTest = null;
+  testPort.postMessage(test);
+}
+
+function testSendMessage() {
+  chrome.runtime.sendMessage('First from interstitial', function(msg) {
+    chrome.runtime.sendMessage('interstitial received: ' + msg);
+    done('testSendMessage');
+  });
+}
+
+function testDisconnectByBackground() {
+  var port = chrome.runtime.connect({
+    name: 'disconnect by background'
+  });
+  port.onDisconnect.addListener(function() {
+    done('testDisconnectByBackground');
+  });
+}
+
+function testDisconnectByInterstitial() {
+  var port = chrome.runtime.connect({
+    name: 'disconnect by interstitial'
+  });
+  port.disconnect();
+  done('testDisconnectByInterstitial');
+}