Minor code style change

src/loaders/MaterialLoader.js

@@ -61,7 +61,7 @@ MaterialLoader.prototype = Object.assign( Object.create( Loader.prototype ), {
 		if ( json.color !== undefined ) material.color.setHex( json.color );
 		if ( json.roughness !== undefined ) material.roughness = json.roughness;
 		if ( json.metalness !== undefined ) material.metalness = json.metalness;
-		if ( json.sheen !== undefined ) material.sheen = (new Color()).setHex( json.sheen );
+		if ( json.sheen !== undefined ) material.sheen = new Color().setHex( json.sheen );
 		if ( json.emissive !== undefined ) material.emissive.setHex( json.emissive );
 		if ( json.specular !== undefined ) material.specular.setHex( json.specular );
 		if ( json.shininess !== undefined ) material.shininess = json.shininess;