Add new PerformanceServerTiming APIs to externs
TypeScript 4.4 added PerformanceServerTiming APIs (https://w3c.github.io/server-timing/) to standard lib.dom.d.ts typings.  This adds those to the default JavaScript externs.
* @see http://w3c-test.org/webperf/specs/ResourceTiming
* @see http://www.w3.org/TR/performance-timeline
* @see http://www.w3.org/TR/user-timing/
+ * @see https://w3c.github.io/server-timing/
*
* @externs
*/
@@ -85,6 +86,16 @@ PerformanceResourceTiming.prototype.decodedBodySize;
/** @type {number|undefined} */
PerformanceResourceTiming.prototype.workerStart;
/** @type {string} */ PerformanceResourceTiming.prototype.nextHopProtocol;
+/** @type {!Array<!PerformanceServerTiming>} */ PerformanceResourceTiming.prototype.serverTiming;
+
+/**
+ * https://w3c.github.io/server-timing/#dom-performanceservertiming
+ * @constructor
+ */
+function PerformanceServerTiming() {}
+/** @type {string} */ PerformanceServerTiming.prototype.name;
+/** @type {number} */ PerformanceServerTiming.prototype.duration;
+/** @type {string} */ PerformanceServerTiming.prototype.description;
/**
* Possible values are 'navigate', 'reload', 'back_forward', and 'prerender'.
