Use @api annotation instead of @todo api

src/ol/format/gpxformat.js

@@ -22,7 +22,7 @@ goog.require('ol.xml');
  *
  * @constructor
  * @extends {ol.format.XMLFeature}
- * @todo api
+ * @api
  */
 ol.format.GPX = function() {
   goog.base(this);
@@ -372,7 +372,7 @@ ol.format.GPX.WPT_PARSERS_ = ol.xml.makeParsersNS(
  * @function
  * @param {ArrayBuffer|Document|Node|Object|string} source Source.
  * @return {ol.Feature} Feature.
- * @todo api
+ * @api
  */
 ol.format.GPX.prototype.readFeature;
 
@@ -403,7 +403,7 @@ ol.format.GPX.prototype.readFeatureFromNode = function(node) {
  * @function
  * @param {ArrayBuffer|Document|Node|Object|string} source Source.
  * @return {Array.<ol.Feature>} Features.
- * @todo api
+ * @api
  */
 ol.format.GPX.prototype.readFeatures;
 
@@ -436,7 +436,7 @@ ol.format.GPX.prototype.readFeaturesFromNode = function(node) {
  * @function
  * @param {ArrayBuffer|Document|Node|Object|string} source Source.
  * @return {ol.proj.Projection} Projection.
- * @todo api
+ * @api
  */
 ol.format.GPX.prototype.readProjection;
 
@@ -811,7 +811,7 @@ goog.inherits(ol.format.GPX.V1_1, ol.format.GPX);
  * @function
  * @param {Array.<ol.Feature>} features Features.
  * @return {ArrayBuffer|Node|Object|string} Result.
- * @todo api
+ * @api
  */
 ol.format.GPX.prototype.writeFeatures;