Bug 1528949 [wpt PR 15460] - HTML: window.focus() sans browsing conte…

…xt, a=testonly

Automatic update from web-platform-tests
HTML: window.focus() sans browsing context

For whatwg/html#4377.
--

wpt-commits: 84a44957233c13fb21f5d97b06db1d89076fb144
wpt-pr: 15460

testing/web-platform/tests/html/browsers/the-window-object/focus.window.js

@@ -0,0 +1,15 @@
+async_test(t => {
+  const input = document.body.appendChild(document.createElement("input"));
+  input.onfocus = t.step_func(() => {
+    const frame = document.body.appendChild(document.createElement("iframe")),
+          frameW = frame.contentWindow;
+    frameW.onfocus = t.unreached_func();
+    frame.remove();
+    frameW.focus();
+    t.step_timeout(() => {
+      assert_equals(document.activeElement, input);
+      t.done();
+    }, 100);
+  });
+  input.focus();
+});