Bug 1665795 [wpt PR 25608] - Fix clear-window-name.https.html fail message, a=testonly

Automatic update from web-platform-tests
Fix clear-window-name.https.html fail message

This test produced different output every time it failed since a
randomly generated string was being passed to assert_equals. This patch
does the same check but prevents the generated string from getting into
the error message so we can include it in our failing test expectations.

Fixed: 1129420
Change-Id: I5cffb6c3dfbe7bb551a626780273291d732f6e1b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2416727
Commit-Queue: Joey Arhar <jarhar@chromium.org>
Reviewed-by: Mason Freed <masonfreed@chromium.org>
Cr-Commit-Position: refs/heads/master@{#808576}

--

wpt-commits: 5a5410b369b69e783fbb526eb997cd70c90ded8e
wpt-pr: 25608

testing/web-platform/tests/html/browsers/windows/clear-window-name.https.html

@@ -29,7 +29,9 @@ function pollResultAndCheck(t, id, expected) {
 
 
       if (res !== "NONE") {
-        t.step(() => assert_equals(res, expected));
+        if (res !== expected) {
+          t.step(() => assert_unreached('Stash result does not equal expected result.'));
+        }
         t.done();
         resolve();
       } else {