GLTFLoader: Replace Array.includes() with Array.indexOf()

examples/js/loaders/GLTFLoader.js

@@ -115,7 +115,7 @@ THREE.GLTFLoader = ( function () {
 
 		register: function ( callback ) {
 
-			if ( ! this.pluginCallbacks.includes( callback ) ) {
+			if ( this.pluginCallbacks.indexOf( callback ) === -1 ) {
 
 				this.pluginCallbacks.push( callback );
 
@@ -127,7 +127,7 @@ THREE.GLTFLoader = ( function () {
 
 		unregister: function ( callback ) {
 
-			if ( this.pluginCallbacks.includes( callback ) ) {
+			if ( this.pluginCallbacks.indexOf( callback ) !== -1 ) {
 
 				this.pluginCallbacks.splice( this.pluginCallbacks.indexOf( callback ), 1 );
 

examples/jsm/loaders/GLTFLoader.js

@@ -179,7 +179,7 @@ var GLTFLoader = ( function () {
 
 		register: function ( callback ) {
 
-			if ( ! this.pluginCallbacks.includes( callback ) ) {
+			if ( this.pluginCallbacks.indexOf( callback ) === -1 ) {
 
 				this.pluginCallbacks.push( callback );
 
@@ -191,7 +191,7 @@ var GLTFLoader = ( function () {
 
 		unregister: function ( callback ) {
 
-			if ( this.pluginCallbacks.includes( callback ) ) {
+			if ( this.pluginCallbacks.indexOf( callback ) !== -1 ) {
 
 				this.pluginCallbacks.splice( this.pluginCallbacks.indexOf( callback ), 1 );