Return null if the layer was not found in the WMTS capabilities

examples/reprojection.js

@@ -99,13 +99,15 @@ fetch(url).then(function(response) {
   return response.text();
 }).then(function(text) {
   var result = parser.read(text);
-  var options = ol.source.WMTS.optionsFromCapabilities(result,
-      {layer: 'OSM_Land_Mask', matrixSet: 'EPSG3413_250m'});
+  var options = ol.source.WMTS.optionsFromCapabilities(result, {
+    layer: 'OSM_Land_Mask',
+    matrixSet: 'EPSG3413_250m'
+  });
   options.crossOrigin = '';
   options.projection = 'EPSG:3413';
   options.wrapX = false;
   layers['wmts3413'] = new ol.layer.Tile({
-    source: new ol.source.WMTS(options)
+    source: new ol.source.WMTS(/** @type {!olx.source.WMTSOptions} */ (options))
   });
 });
 

examples/wmts-hidpi.js

@@ -34,6 +34,6 @@ fetch(capabilitiesUrl).then(function(response) {
   });
   options.tilePixelRatio = tilePixelRatio;
   map.addLayer(new ol.layer.Tile({
-    source: new ol.source.WMTS(options)
+    source: new ol.source.WMTS(/** @type {!olx.source.WMTSOptions} */ (options))
   }));
 });

examples/wmts-layer-from-capabilities.js

@@ -12,8 +12,10 @@ fetch('data/WMTSCapabilities.xml').then(function(response) {
   return response.text();
 }).then(function(text) {
   var result = parser.read(text);
-  var options = ol.source.WMTS.optionsFromCapabilities(result,
-      {layer: 'layer-7328', matrixSet: 'EPSG:3857'});
+  var options = ol.source.WMTS.optionsFromCapabilities(result, {
+    layer: 'layer-7328',
+    matrixSet: 'EPSG:3857'
+  });
 
   map = new ol.Map({
     layers: [
@@ -23,7 +25,7 @@ fetch('data/WMTSCapabilities.xml').then(function(response) {
       }),
       new ol.layer.Tile({
         opacity: 1,
-        source: new ol.source.WMTS(options)
+        source: new ol.source.WMTS(/** @type {!olx.source.WMTSOptions} */ (options))
       })
     ],
     target: 'map',