code: function() {
      var tree = this._super.treeForApp.apply(this, arguments);
      var app = findHost(this);
  
      if (app && app.options && app.options.assetLoader && app.options.assetLoader.noManifest) {
        tree = new Funnel(tree, {
          exclude: [
            'config/asset-manifest.js',
            'instance-initializers/load-asset-manifest.js'
          ]
        });
      }
  
      return tree;
    }
docs: If the app has specified `noManifest` to be generated, then we don't
  include the shim for the manifest and the service initializer.
  
  @override