AngularJS ng-bind-html with filter

<!DOCTYPE html>
<html>

  <head>
    <script data-require="jquery@*" data-semver="2.1.1" src="//cdnjs.cloudflare.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
    <script data-require="angular.js@*" data-semver="1.2.13" src="http://code.angularjs.org/1.2.13/angular.js"></script>
    <script data-require="angular-sanitize@*" data-semver="1.2.13" src="http://code.angularjs.org/1.2.13/angular-sanitize.js"></script>
    <link rel="stylesheet" href="style.css" />
    <script src="script.js"></script>
  </head>

  <body ng-app="test" ng-controller="HomeCtrl">
    <h1>Test </h1>
    <div ng-bind-html="myHtml | addTargetBlank"></div>
  </body>

</html>

// Code goes here

angular.module('test', ['ngSanitize'])
.filter('addTargetBlank', function(){
  return function(x) {
    var tree = angular.element('<div>'+x+'</div>');//defensively wrap in a div to avoid 'invalid html' exception
    tree.find('a').attr('target', '_blank'); //manipulate the parse tree
    return angular.element('<div>').append(tree).html(); //trick to have a string representation
  }
})

.controller('HomeCtrl', function($scope){
  $scope.myHtml = 'test html content 1 <a href="#">click here</a>, test html content 2 <a href="#">click here</a>, test html content 3 <a href="#">click here</a>';
})
;

/* Styles go here */