testWebTestButton() {
    if (userAgent.GECKO) {
      // TODO(robbyw): Figure out why this is flaky and fix it.
      return;
    }

    let height;
    let width;

    mockWindowOpen(
        ANCHOR_URL,
        new ArgumentMatcher(
            (options) => !asserts.findDifferences(options, {
              target: '_blank',
              width: width,
              height: height,
              toolbar: true,
              scrollbars: true,
              location: true,
              statusbar: false,
              menubar: true,
              resizable: true,
              noreferrer: false,
              noopener: false,
            }),
            '2nd arg: window.open() options'),
        window);

    mockCtrl.$replayAll();
    setUpAnchor(ANCHOR_URL, ANCHOR_TEXT);
    createAndShow();

    // Measure viewport after opening dialog because that might cause scrollbars
    // to appear and reduce the viewport size.
    const size = dom.getViewportSize(window);
    width = Math.max(size.width - 50, 50);
    height = Math.max(size.height - 50, 50);

    /** @suppress {visibility} suppression added to enable type checking */
    const testLink = testingDom.findTextNode(
        messages.MSG_TEST_THIS_LINK, dialog.dialogInternal_.getElement());
    testingEvents.fireClickSequence(testLink.parentNode);

    mockCtrl.$verifyAll();
  }
Test that clicking on the test button opens a new window with the correct
options.
@suppress {checkTypes} suppression added to enable type checking