ColladaLoader: Hack for Mesh.parse showstopper. Fixes #5828.

examples/js/loaders/ColladaLoader.js

@@ -2805,6 +2805,14 @@ THREE.ColladaLoader = function () {
 
 		this.geometry3js = new THREE.Geometry();
 
+		if ( this.vertices === null ) {
+
+			// TODO (mrdoob): Study case when this is null (carrier.dae)
+
+			return this;
+
+		}
+
 		var vertexData = sources[ this.vertices.input['POSITION'].source ].data;
 
 		for ( var i = 0; i < vertexData.length; i += 3 ) {