Use XHR by default

externs/olx.js

@@ -4193,6 +4193,7 @@ olx.source.ClusterOptions.prototype.wrapX;
 
 /**
  * @typedef {{preemptive: (boolean|undefined),
+ *     jsonp: (boolean|undefined),
  *     tileJSON: (TileJSON|undefined),
  *     url: (string|undefined)}}
  * @api
@@ -4200,6 +4201,15 @@ olx.source.ClusterOptions.prototype.wrapX;
 olx.source.TileUTFGridOptions;
 
 
+/**
+ * Use JSONP with callback to load the TileJSON. Useful when the server
+ * does not support CORS. Default is `false`.
+ * @type {boolean|undefined}
+ * @api
+ */
+olx.source.TileUTFGridOptions.prototype.jsonp;
+
+
 /**
  * If `true` the TileUTFGrid source loads the tiles based on their "visibility".
  * This improves the speed of response, but increases traffic.