Refactor the implementation of the webNavigation extension API.

chrome/test/data/extensions/api_test/webnavigation/prerender/test_prerender.js

 // Copyright 2013 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.
 
 onload = function() {
   var getURL = chrome.extension.getURL;
   var URL_LOAD =
       "http://127.0.0.1:PORT/prerender/prerender_loader.html";
   var URL_TARGET =
       "http://127.0.0.1:PORT/prerender/prerender_page.html";
   chrome.tabs.create({"url": "about:blank"}, function(tab) {
     var tabId = tab.id;
     chrome.test.getConfig(function(config) {
       var fixPort = function(url) {
         return url.replace(/PORT/g, config.testServer.port);
       };
       URL_LOAD = fixPort(URL_LOAD);
       URL_TARGET = fixPort(URL_TARGET);
 
       chrome.test.runTests([
         // A prerendered tab replaces the current tab.
         function prerendered() {
           expect([
             { label: "a-onBeforeNavigate",
               event: "onBeforeNavigate",
               details: { frameId: 0,
                          parentFrameId: -1,
-                         processId: 0,
+                         processId: -1,
                          tabId: 0,
                          timeStamp: 0,
                          url: URL_LOAD }},
             { label: "a-onCommitted",
               event: "onCommitted",
               details: { frameId: 0,
                          processId: 0,
                          tabId: 0,
                          timeStamp: 0,
                          transitionQualifiers: [],
@@ skipping 10 matching lines @@
               event: "onCompleted",
               details: { frameId: 0,
                          processId: 0,
                          tabId: 0,
                          timeStamp: 0,
                          url: URL_LOAD }},
             { label: "b-onBeforeNavigate",
               event: "onBeforeNavigate",
               details: { frameId: 0,
                          parentFrameId: -1,
-                         processId: 1,
+                         processId: -1,
                          tabId: 1,
                          timeStamp: 0,
                          url: URL_TARGET }},
             { label: "b-onCommitted",
               event: "onCommitted",
               details: { frameId: 0,
                          processId: 1,
                          tabId: 1,
                          timeStamp: 0,
                          transitionQualifiers: [],
@@ skipping 22 matching lines @@
               navigationOrder("b-"),
               [ "a-onCompleted", "b-onCompleted", "onTabReplaced" ]]);
 
           // Notify the api test that we're waiting for the user.
           chrome.test.notifyPass();
         },
       ]);
     });
   });
 };