Add 'platform' to NavigatorUAData
References:
@@ -72,6 +72,9 @@ NavigatorUAData.prototype.brands;
/** @type {boolean} */
NavigatorUAData.prototype.mobile;
+/** @type {string} */
+NavigatorUAData.prototype.platform;
+
/**
* @param {!Array<string>} hints
* @return {!Promise<!UADataValues>}
