testPostMessagePolyfillDoesNotPumpCallbackQueueIfMessageIsIncorrect() {
    // EDGE/IE does not use the postMessage polyfill.
    if (browser.isIE() || browser.isEdge()) {
      return;
    }

    // Force postMessage polyfill for setImmediate.
    propertyReplacer.set(window, 'setImmediate', undefined);
    propertyReplacer.set(window, 'MessageChannel', undefined);

    let atNextTick = new GoogPromise(nextTick);

    const frame = dom.getElementsByTagName(TagName.IFRAME)[0];
    frame.contentWindow.postMessage(
        'bogus message',
        window.location.protocol + '//' + window.location.host);

    // The test passes if no error is ever reported by the <iframe>, as would
    // happen if the queue was pumped without an callbacks to run.
    frame.contentWindow.onerror = window.onerror;

    return atNextTick.thenAlways(() => {
      dom.removeNode(frame);
    });
  }
Test a scenario in which the iframe used by the postMessage polyfill gets a
message that does not have match what is expected. In this case, the
polyfill should not try to invoke a callback (which would result in an
error because there would be no callbacks in the linked list).

TODO(nickreid): Delete this test? It's testing for a an adversarial input
case and depend on deep implementation details.