Modified two extension tests to not be dependent on low-latency DOM timers

chrome/test/data/extensions/api_test/window_open/panel/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.
 
-var panelWindowId = 0;
-
 // This function is called by the panel during the test run.
 function panelCallback() {
   // We have now added a panel so the total counts is 2 (browser + panel).
   chrome.test.assertEq(2, chrome.extension.getViews().length);
-  // Verify that we're able to get the view of the panel by its window id.
-  chrome.test.assertEq(1,
-      chrome.extension.getViews({"windowId": panelWindowId}).length);
   chrome.test.notifyPass();
 }
 
 chrome.test.runTests([
   function openPanel() {
     chrome.test.listenOnce(chrome.windows.onCreated, function(window) {
       chrome.test.assertTrue(window.width > 0);
       chrome.test.assertTrue(window.height > 0);
       chrome.test.assertEq("panel", window.type);
       chrome.test.assertTrue(!window.incognito);
     });
     chrome.windows.create(
         { 'url': chrome.extension.getURL('panel.html'), 'type': 'panel' },
         function(win) {
             chrome.test.assertEq('panel', win.type);
             chrome.test.assertEq(true, win.alwaysOnTop);
-            panelWindowId = win.id;
+            // Verify that we're able to get the view of the panel by its
+            // window id.
+            chrome.test.assertEq(1,
+                chrome.extension.getViews({"windowId": win.id}).length);

[not at google - send to devlin, 2015/04/24 22:18:10]

This test still has a small problem, where if panelCallback does come back
first, the test will pass even if this check fails (due to the test legitimately
failing, for example). Perhaps leave the panelWindowId variable at the top, some
way of knowing when both callbacks have been run, at which point you make those
assertions about getViews then notifyPass()? I'm imagining something like
this...

var panelWindowId = -1;
var panelLoaded = false;
function maybeDone() {
  if (panelWindowId >= 0 && panelLoaded) {
    ...
  }
}

function panelCallback() {
  panelLoaded = true;
  maybeDone();
}

chrome.windows.create(function() {
  panelWindowId = win.id;
  maybeDone();
});

             // The panel will call back to us through panelCallback (above).
         });
   }
 ]);