Add specs for jqXHR object returned by $.ajax

The tests are corresponding to the syntax listed in its website:
http://api.jquery.com/jQuery.ajax/#jqXHR

jquery/jquery-tests.ts

@@ -151,7 +151,38 @@ function test_ajax() {
         dataType: "script"
     });
 
-    // treat $.ajax() as a promise (as of 1.8)
+    // Test the jqXHR object returned by $.ajax() as of 1.5
+    // More details: http://api.jquery.com/jQuery.ajax/#jqXHR
+
+    // done method
+    $.ajax({
+        url: "test.js"
+    }).done((data, textStatus, jqXHR) => {
+        console.log(data, textStatus, jqXHR);
+    });
+
+    // fail method
+    $.ajax({
+        url: "test.js"
+    }).fail((jqXHR, textStatus, errorThrown) => {
+        console.log(jqXHR, textStatus, errorThrown);
+    });
+
+    // always method with successful request
+    $.ajax({
+        url: "test.js"
+    }).always((data, textStatus, jqXHR) => {
+        console.log(data, textStatus, jqXHR);
+    });
+
+    // always method with failed request
+    $.ajax({
+        url: "test.js"
+    }).always((jqXHR, textStatus, errorThrown) => {
+        console.log(jqXHR, textStatus, errorThrown);
+    });
+
+    // then method (as of 1.8)
     $.ajax({
         url: "test.js"
     }).then((data, textStatus, jqXHR) => {