Simplified check for XMLHttpRequest (saving a few bytes) and fixed load()-test

src/ajax/ajax.js

@@ -132,7 +132,7 @@ jQuery.fn.extend({
 });
 
 // If IE is used, create a wrapper for the XMLHttpRequest object
-if ( jQuery.browser.msie && typeof XMLHttpRequest == "undefined" )
+if ( !window.XMLHttpRequest )
 	XMLHttpRequest = function(){
 		return new ActiveXObject("Microsoft.XMLHTTP");
 	};

src/ajax/ajaxTest.js

@@ -70,8 +70,8 @@ test("load(String, Object, Function) - inject without callback", function() {
 test("load(String, Object, Function) - check scripts", function() {
 	expect(7);
 	stop();
-	var testFoo = undefined;
-	foobar = null;
+	window.testFoo = undefined;
+	window.foobar = null;
 	var verifyEvaluation = function() {
 	  ok( foobar == "bar", 'Check if script src was evaluated after load' );
 	  ok( $('#ap').html() == 'bar', 'Check if script evaluation has modified DOM');