Add missing jsonpCallbackParam option in angular externs
This option was added in version 1.6, see:
https://docs.angularjs.org/guide/migration#migrate1.5to1.6-ng-services-$http
@@ -1564,6 +1564,9 @@ angular.$http.Config.prototype.data
/** @type {(Object<?string|undefined>|undefined)} */
angular.$http.Config.prototype.headers;
+/** @type {(string|undefined)} */
+angular.$http.Config.prototype.jsonpCallbackParam;
+
/** @type {(string|undefined)} */
angular.$http.Config.prototype.method;
