Update references to the extension messaging APIs to point to the "runtime"

chrome/test/data/extensions/api_test/native_messaging/test.js

 // Copyright (c) 2012 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.test.getConfig(function(config) {
     chrome.test.runTests([
 
       function sendMessageWithCallback() {
         var message = {"text": "Hi there!", "number": 3};
-        chrome.extension.sendNativeMessage(
+        chrome.runtime.sendNativeMessage(
             'echo.py', message,
             chrome.test.callbackPass(function(nativeResponse) {
           var expectedResponse = {"id": 1, "echo": message};
           chrome.test.assertEq(expectedResponse, nativeResponse);
         }));
       },
 
       // The goal of this test, is just not to crash.
       function sendMessageWithoutCallback() {
         var message = {"text": "Hi there!", "number": 3};
-        chrome.extension.sendNativeMessage('echo.py', message);
+        chrome.runtime.sendNativeMessage('echo.py', message);
         chrome.test.succeed(); // Mission Complete
       },
 
       function connect() {
         var messagesToSend = [{"text": "foo"},
                               {"text": "bar", "funCount": 9001},
                               {}];
         var expectedResponses = [{"id": 1, "echo": messagesToSend[0]},
                                  {"id": 2, "echo": messagesToSend[1]},
                                  {"id": 3, "echo": messagesToSend[2]}];
         var currentMessage = 0;
 
-        port = chrome.extension.connectNative('echo.py',
+        port = chrome.runtime.connectNative('echo.py',
                                               messagesToSend[currentMessage]);
         port.onMessage.addListener(function(message) {
           chrome.test.assertEq(expectedResponses[currentMessage], message);
           currentMessage++;
 
           if (currentMessage == expectedResponses.length)
             chrome.test.notifyPass();
           else
             port.postMessage(messagesToSend[currentMessage]);
         });
       }
     ]);
 });