Adding Internals.numberOfLiveAXObjects to test for leaking AXObjects

LayoutTests/resources/leak-check.js

 // include resources/js-test.js before this file.
 
 function getCounterValues(callback) {
     testRunner.resetTestHelperControllers();
     asyncGC(function() {
-        var ret = {'numberOfLiveDocuments': window.internals.numberOfLiveDocuments()};
+        var ret = {
+          'numberOfLiveDocuments': window.internals.numberOfLiveDocuments(),
+          'numberOfLiveAXObjects': window.internals.numberOfLiveAXObjects()
+        };
 
         var refCountedInstances = JSON.parse(window.internals.dumpRefCountedInstanceCounts());
         for (typename in refCountedInstances)
             ret['numberOfInstances-'+typename] = refCountedInstances[typename];
 
         callback(ret);
     });
 
 }
 
@@ skipping 57 matching lines @@
 
 function htmlToUrl(html) {
     return 'data:text/html;charset=utf-8,' + html;
 }
 
 function grabScriptText(id) {
     return document.getElementById(id).innerText;
 }
 
 // include fast/js/resources/js-test-post.js after this file.