Pixi error Uncaught TypeError: Cannot read property 'indexOf' of null

[mtermoul]

I had this spine animation which use to work fine when I used Pixi 2.1 but it's throwing this error when I use Pixi 2.2.

 

Uncaught TypeError: Cannot read property 'indexOf' of null

 

The animation is loaded as 

 

    var assetsToLoader = ["/animations/home/bird.atlas.json",

                                         "/animations/home/bird.anim.json"];

 

    // create a new loader

    loader = new PIXI.AssetLoader(assetsToLoader);

 

    // use callback

    loader.onComplete = onAssetsLoaded

 

    //begin load

    loader.load();

 

I am using animation created using Spine 1.9! hope that's still supported with Pixi.