Add missing aoMap and aoMapIntensity to Material.toJSON()

src/materials/Material.js

@@ -176,6 +176,14 @@ Material.prototype = Object.assign( Object.create( EventDispatcher.prototype ),
 		if ( this.map && this.map.isTexture ) data.map = this.map.toJSON( meta ).uuid;
 		if ( this.alphaMap && this.alphaMap.isTexture ) data.alphaMap = this.alphaMap.toJSON( meta ).uuid;
 		if ( this.lightMap && this.lightMap.isTexture ) data.lightMap = this.lightMap.toJSON( meta ).uuid;
+
+		if ( this.aoMap && this.aoMap.isTexture ) {
+
+			data.aoMap = this.aoMap.toJSON( meta ).uuid;
+			data.aoMapIntensity = this.aoMapIntensity;
+
+		}
+
 		if ( this.bumpMap && this.bumpMap.isTexture ) {
 
 			data.bumpMap = this.bumpMap.toJSON( meta ).uuid;