old_contents: Template.afArrayField_bootstrap3.helpers({
    panelClass: function() {
      return this.atts.panelClass || 'panel-default';
    },
    headingClass: function() {
      return return this.atts.headingClass || '';
    }
  });
  
new_contents: Template.afArrayField_bootstrap3.helpers({
    panelClass: function() {
      return this.atts.panelClass || 'panel-default';
    },
    headingClass: function() {
      return this.atts.headingClass || '';
    }
  });
  
subject: fix Unexpected token (6:11)