Sync requestFullscreen() and exitFullscreen() algorithms with the spec

third_party/WebKit/LayoutTests/fullscreen/api/element-request-fullscreen-two-iframes.html

Index: third_party/WebKit/LayoutTests/fullscreen/api/element-request-fullscreen-two-iframes.html
diff --git a/third_party/WebKit/LayoutTests/fullscreen/api/element-request-fullscreen-two-iframes.html b/third_party/WebKit/LayoutTests/fullscreen/api/element-request-fullscreen-two-iframes.html
index c9b0ed6a8eb4def88bb3ebf33614d6a4746226fe..688e6692dabf2784dc4003b8aa6a1c3970d688b9 100644
--- a/third_party/WebKit/LayoutTests/fullscreen/api/element-request-fullscreen-two-iframes.html
+++ b/third_party/WebKit/LayoutTests/fullscreen/api/element-request-fullscreen-two-iframes.html
@@ -18,15 +18,15 @@ async_test(t => {
   // Expect first a fullscreenchange event for the second (!) request, then a
   // fullscreenerror event for the first request. TODO(foolip): Remove the
   // Fullscreen hierarchy restrictions. https://crbug.com/627792
-  a.contentDocument.onfullscreenerror = t.step_func(() => {
-    b.contentDocument.onfullscreenchange = t.step_func_done(() => {
-      assert_equals(document.fullscreenElement, b, 'fullscreenElement');
-      assert_equals(a.contentDocument.fullscreenElement, null, 'fullscreenElement in iframe a');
-      assert_equals(b.contentDocument.fullscreenElement, b.contentDocument.body, 'fullscreenElement in iframe b');
+  a.contentDocument.onfullscreenchange = t.step_func_done(() => {
+    assert_equals(document.fullscreenElement, a, 'fullscreenElement');
+    assert_equals(a.contentDocument.fullscreenElement, a.contentDocument.body, 'fullscreenElement in iframe a');
+    b.contentDocument.onfullscreenerror = t.step_func(() => {
+      assert_equals(b.contentDocument.fullscreenElement, null, 'fullscreenElement in iframe b');
     });
   });
-  a.contentDocument.onfullscreenchange = t.unreached_func('fullscreenchange event in iframe a');
-  b.contentDocument.onfullscreenerror = t.unreached_func('fullscreenerror event in iframe b');
+  a.contentDocument.onfullscreenerror = t.unreached_func('fullscreenerror event in iframe a');
+  b.contentDocument.onfullscreenchange = t.unreached_func('fullscreenchange event in iframe b');
 
   trusted_click(t.step_func(() => {
     b.contentDocument.body.requestFullscreen();