Adding XYZOptions to objectliterals.jsdoc

I remain uncertain about when to use the @exportClass annotation and when to use the @exportSymbol.  osmsource.exports seems to get away with simply @exportSymbol, but many other sources use @exportProperty.

src/objectliterals.jsdoc

@@ -605,6 +605,24 @@
  * @property {Array.<string>|undefined} urls Urls.
  */
 
+/**
+ * @typedef {Object} ol.source.XYZOptions
+ * @property {Array.<ol.Attribution>|undefined} attributions Attributions.
+ * @property {null|string|undefined} crossOrigin Cross origin setting for image
+ *     requests.
+ * @property {ol.Extent|undefined} extent Extent.
+ * @property {string|undefined} logo Logo.
+ * @property {ol.ProjectionLike} projection Projection.
+ * @property {number} maxZoom Max zoom.
+ * @property {number|undefined} minZoom Unsupported (TODO: remove this).
+ * @property {ol.TileUrlFunctionType|undefined} tileUrlFunction Optional
+ *     function to get tile URL given a tile coordinate and the projection.
+ *     Required if url or urls are not provided.
+ * @property {string|undefined} url URL template.  Must include '{x}', '{y}',
+ *     and '{z}' placeholders.
+ * @property {Array.<string>|undefined} urls An array of URL templates.
+ */
+
 /**
  * @typedef {Object} ol.style.IconOptions
  * @property {string|ol.expr.Expression} url Icon image url.

src/ol/source/xyzsource.exports

@@ -1 +1 @@
-@exportSymbol ol.source.XYZ
+@exportClass ol.source.XYZ ol.source.XYZOptions

src/ol/source/xyzsource.js

@@ -1,5 +1,4 @@
 goog.provide('ol.source.XYZ');
-goog.provide('ol.source.XYZOptions');
 
 goog.require('ol.Attribution');
 goog.require('ol.Projection');
@@ -10,21 +9,6 @@ goog.require('ol.source.TileImage');
 goog.require('ol.tilegrid.XYZ');
 
 
-/**
- * @typedef {{attributions: (Array.<ol.Attribution>|undefined),
- *            crossOrigin: (string|undefined),
- *            extent: (ol.Extent|undefined),
- *            logo: (string|undefined),
- *            maxZoom: number,
- *            minZoom: (number|undefined),
- *            projection: (ol.Projection|undefined),
- *            tileUrlFunction: (ol.TileUrlFunctionType|undefined),
- *            url: (string|undefined),
- *            urls: (Array.<string>|undefined)}}
- */
-ol.source.XYZOptions;
-
-
 
 /**
  * @constructor