LOD: Honor .autoUpdate in toJSON().

src/loaders/ObjectLoader.js

@@ -964,6 +964,8 @@ ObjectLoader.prototype = Object.assign( Object.create( Loader.prototype ), {
 
 		if ( data.type === 'LOD' ) {
 
+			if ( data.autoUpdate !== undefined ) object.autoUpdate = data.autoUpdate;
+
 			var levels = data.levels;
 
 			for ( var l = 0; l < levels.length; l ++ ) {

src/objects/LOD.js

@@ -161,6 +161,8 @@ LOD.prototype = Object.assign( Object.create( Object3D.prototype ), {
 
 		var data = Object3D.prototype.toJSON.call( this, meta );
 
+		if ( this.autoUpdate === false ) data.object.autoUpdate = false;
+
 		data.object.levels = [];
 
 		var levels = this.levels;