XHRLoader is the deprecated one apparently ...

examples/js/loaders/FBXLoader.js

@@ -36,7 +36,7 @@
 
 			var scope = this;
 
-			var loader = new THREE.XHRLoader( scope.manager );
+			var loader = new THREE.FileLoader( scope.manager );
 			// loader.setCrossOrigin( this.crossOrigin );
 			loader.load( url, function ( text ) {
 
@@ -597,7 +597,7 @@
 
 		loadFile: function ( url, onLoad, onProgress, onError, responseType ) {
 
-			var loader = new THREE.XHRLoader( this.manager );
+			var loader = new THREE.FileLoader( this.manager );
 
 			loader.setResponseType( responseType );