Track all extension frames in ProcessManager, inspect extensionoptions

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

 // Copyright 2015 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.
 
 chrome.runtime.onMessage.addListener(function(message, sender, sendResponse) {
-  if (message.type == "xhr") {
-    var xhr = new XMLHttpRequest();
-    xhr.open(message.method, message.url);
-    xhr.send();
-  } else {
-    console.error("Unknown message: " + JSON.stringify(message));
-  }
+  chrome.test.assertEq('msg from tab', message);
+  sendResponse('Reply here');
 });
+
+var port = chrome.runtime.connect();
+port.postMessage('Hello from content script');
+port.disconnect();