Fix xrDevice_requestSession_no_mode to test for a throw, not a rejection

tests/wpt/metadata/MANIFEST.json

@@ -727499,7 +727499,7 @@
    "testharness"
   ],
   "webxr/xrDevice_requestSession_no_mode.https.html": [
-   "de77b38c868e3b5dad88b8eface770b16b5f16c1",
+   "5ef249c58186131f8e467da48cfafebe65df9adf",
    "testharness"
   ],
   "webxr/xrDevice_requestSession_non_immersive_no_gesture.https.html": [

tests/wpt/metadata/webxr/xrDevice_requestSession_no_mode.https.html.ini

@@ -1,4 +0,0 @@
-[xrDevice_requestSession_no_mode.https.html]
-  [Requesting a session with no mode rejects]
-    expected: FAIL
-

tests/wpt/web-platform-tests/webxr/xrDevice_requestSession_no_mode.https.html

@@ -11,11 +11,10 @@
         return navigator.xr.test.simulateDeviceConnection(VALID_NON_IMMERSIVE_DEVICE)
           .then( (controller) => new Promise((resolve) => {
             navigator.xr.test.simulateUserActivation( () => {
-              resolve(promise_rejects(
-                t,
-                new TypeError(),
-                navigator.xr.requestSession()
-              ))
+              t.step_func(() => {
+                assert_throws(new TypeError(), () => navigator.xr.requestSession())
+              })
+              resolve()
             });
           }));
       });