Function applyResponse

src/impression.js:242–274

* parse the response back from ad server * Set for analytics purposes * @param {!Window} win * @param {?JsonObject} response

(win, response)

 * @param {?JsonObject} response
 */
function applyResponse(win, response) {
  if (!response) {
    return;
  }

  const adLocation = response['location'];
  const adTracking = response['tracking_url'];

  // If there is a tracking_url, need to track it
  // Otherwise track the location
  const trackUrl = adTracking || adLocation;

  if (trackUrl && !isProxyOrigin(trackUrl)) {
    // To request the provided trackUrl for tracking purposes.
    new Image().src = trackUrl;
  }

  // Replace the location href params with new location params we get (if any).
  if (adLocation) {
    if (!win.history.replaceState) {
      return;
    }

    const viewer = Services.viewerForDoc(win.document.documentElement);
    const currentHref = WindowInterface.getLocation(win).href;
    const url = parseUrlDeprecated(adLocation);
    const params = parseQueryString(url.search);
    const newHref = addParamsToUrl(currentHref, params);
    // TODO: Avoid overwriting the fragment parameter.
    win.history.replaceState(null, '', newHref);
    viewer.maybeUpdateFragmentForCct();
  }
}

/**
 * Return a promise that whether appending extra url params to outgoing link is