AngularJS submitIt directive

<!DOCTYPE html>
<html ng-app="MyApp">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <link data-require="bootstrap-css@3.0.0" data-semver="3.0.0" rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css" />
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="angular.js@1.1.x" src="https://ajax.googleapis.com/ajax/libs/angularjs/1.1.5/angular.js" data-semver="1.1.5"></script>
    <script src="app.js"></script>
    <script src="submitIt.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <div class="container text-center">
      <p>&nbsp;</p>
      <button class="btn btn-primary" ng-click="submit = true">Take me to Google.com</button>
    </div>
    <form target="_top" submit-it="submit" si-method="get" si-action="http://www.google.com"></form>
  </body>

</html>

var app = angular.module('MyApp', ['submitIt']);

app.controller('MainCtrl', function($scope) {

  // nothing here

});

angular.module('submitIt', [])

/**
 * @ngdoc directive
 * @description form submission trigger
 *
 * @param {boolean} submit-it submit form on `true`
 * @param {string}  si-action submit action(optional)
 * @param {string}  si-method submit method(optional)
 */
.directive('submitIt', [
         '$timeout',
function ($timeout) {
  return {
    restrict: 'A',
    link: function postLink(scope, iElm, iAttrs) {
      var _submitWatch = scope.$watch(iAttrs.submitIt, _onSubmitWatch),
          _savedAction, _savedMethod;

      iAttrs.$observe('siAction', function (val) {
        if (val) {
          _savedAction = val;
        }
      });

      iAttrs.$observe('siMethod', function (val) {
        if (val) {
          _savedMethod = val;
        }
      });

      function _onSubmitWatch(submit) {
        if (submit && iElm[0].tagName === 'FORM') {
          if (_savedAction) {
            iElm.attr('action', _savedAction);
          }

          if (_savedMethod) {
            iElm.attr('method', _savedMethod);
          }

          $timeout(function () {
            iElm[0].submit();
          });
          _submitWatch();
        }
      }
    }
  };
}]);