GLTFLoader: Revert automatic node naming.

Author: donmccurdy

examples/js/loaders/GLTFLoader.js

@@ -2890,8 +2890,6 @@ THREE.GLTFLoader = ( function () {
 
 	};
 
-	var nextNodeIndex = 1;
-
 	/**
 	 * Specification: https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#nodes-and-hierarchy
 	 * @param {number} nodeIndex
@@ -2981,10 +2979,6 @@ THREE.GLTFLoader = ( function () {
 
 				node.name = THREE.PropertyBinding.sanitizeNodeName( nodeDef.name );
 
-			} else {
-
-				node.name = 'gltfNode' + ( nextNodeIndex++ );
-
 			}
 
 			if ( nodeDef.extras ) node.userData = nodeDef.extras;