Convert cross-origin fullscreen test to use testdriver

diff --git a/fullscreen/api/element-request-fullscreen-cross-origin-manual.sub.html b/fullscreen/api/element-request-fullscreen-cross-origin.sub.html
similarity index 98%
rename from fullscreen/api/element-request-fullscreen-cross-origin-manual.sub.html
rename to fullscreen/api/element-request-fullscreen-cross-origin.sub.html
index c01bd9a..c233fc2 100644
--- a/fullscreen/api/element-request-fullscreen-cross-origin-manual.sub.html
+++ b/fullscreen/api/element-request-fullscreen-cross-origin.sub.html

@@ -80,7 +80,7 @@
     {"action": "requestFullscreen", "fullscreen": {"name": iframe_to_fullscreen}}, "*");
   await ready();
 
-  function test_report(report) {
+  let test_report = t.step_func(function (report) {
     let expected = expected_events[report.frame];
 
     assert_equals(report.events.length, expected.length, "Number of events");
@@ -93,7 +93,7 @@
     } else {
       assert_true(report.fullscreenElementIsNull, "No event fired, fullscreenElement is null");
     }
-  }
+  })
 
   let reports = new Promise(resolve => {
     let report_count = 0;

diff --git a/fullscreen/api/resources/recursive-iframe-fullscreen.html b/fullscreen/api/resources/recursive-iframe-fullscreen.html
index f28afdd..aa2a041 100644
--- a/fullscreen/api/resources/recursive-iframe-fullscreen.html
+++ b/fullscreen/api/resources/recursive-iframe-fullscreen.html

@@ -1,6 +1,8 @@
 <!DOCTYPE html>
 <meta charset="utf-8">
 <title>Recursive IFrame Fullscreen API success reporter</title>
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
 <body>
 <script>
 let child_frame = null;
@@ -40,6 +42,8 @@
         container.removeChild(button);
     };
     container.insertBefore(button, container.firstChild);
+    test_driver.set_test_context(window.top);
+    test_driver.click(button);
 }
 
 function go_fullscreen() {