crossOrigin defaults to null

src/ol/source/bingmapssource.js

@@ -23,6 +23,7 @@ goog.require('ol.tilegrid.XYZ');
 ol.source.BingMaps = function(bingMapsOptions) {
 
   goog.base(this, {
+    crossOrigin: 'anonymous',
     opaque: true,
     projection: ol.projection.get('EPSG:3857')
   });

src/ol/source/imagesource.js

@@ -53,7 +53,7 @@ ol.source.ImageSource = function(options) {
    * @type {?string}
    */
   this.crossOrigin_ =
-      goog.isDef(options.crossOrigin) ? options.crossOrigin : 'anonymous';
+      goog.isDef(options.crossOrigin) ? options.crossOrigin : null;
 
   /**
    * @private

src/ol/source/imagetilesource.js

@@ -55,7 +55,7 @@ ol.source.ImageTileSource = function(options) {
    * @type {?string}
    */
   this.crossOrigin_ =
-      goog.isDef(options.crossOrigin) ? options.crossOrigin : 'anonymous';
+      goog.isDef(options.crossOrigin) ? options.crossOrigin : null;
 
   /**
    * @private

src/ol/source/mapquestsource.js

@@ -26,6 +26,7 @@ ol.source.MapQuestOSM = function() {
 
   goog.base(this, {
     attributions: attributions,
+    crossOrigin: 'anonymous',
     opaque: true,
     maxZoom: 28,
     url: 'http://otile{1-4}.mqcdn.com/tiles/1.0.0/osm/{z}/{x}/{y}.jpg'
@@ -54,6 +55,7 @@ ol.source.MapQuestOpenAerial = function() {
 
   goog.base(this, {
     attributions: attributions,
+    crossOrigin: 'anonymous',
     maxZoom: 18,
     opaque: true,
     url: 'http://oatile{1-4}.mqcdn.com/tiles/1.0.0/sat/{z}/{x}/{y}.jpg'

src/ol/source/openstreetmapsource.js

@@ -18,6 +18,7 @@ ol.source.OpenStreetMap = function() {
 
   goog.base(this, {
     attributions: [attribution],
+    crossOrigin: 'anonymous',
     opaque: true,
     maxZoom: 18,
     url: 'http://{a-c}.tile.openstreetmap.org/{z}/{x}/{y}.png'

src/ol/source/stamensource.js

@@ -106,6 +106,7 @@ ol.source.Stamen = function(options) {
 
   goog.base(this, {
     attributions: ol.source.STAMEN_ATTRIBUTIONS,
+    crossOrigin: 'anonymous',
     maxZoom: providerConfig.maxZoom,
     // FIXME uncomment the following when tilegrid supports minZoom
     //minZoom: providerConfig.minZoom,

src/ol/source/tilejsonsource.js

@@ -46,6 +46,7 @@ goog.exportSymbol('grid', grid);
 ol.source.TileJSON = function(tileJsonOptions) {
 
   goog.base(this, {
+    crossOrigin: tileJsonOptions.crossOrigin,
     projection: ol.projection.get('EPSG:3857')
   });