title: Aria-checked value not switching from true to false when checking the checkbox
body: <p>My screen reader <strong>JAWS 17</strong> is reading Checkbox not checked when I am on the checkbox even though I check it. </p>
  
  <p>I debugged the issue and found out that the <strong>aria-checked="false"</strong> is not switching to <strong>aria-checked="true"</strong> when I check it.</p>
  
  <p>I am using Google Chrome 58.0.3029.110 (64-bit)</p>
  
  <p>HTML</p>
  
  <pre><code>&lt;modified-input
           enter-space-press="checked(row)"
           disabled="!row.enabled"
           ng-click="check(row)"&gt;
   &lt;/modified-input&gt;
  </code></pre>
  
  <p>Directive </p>
  
  <pre><code>function modifiedInput($window, $rootScope, _) {
          return {
              restrict: 'E',
              scope: {
                  value:'=?',
                  disabled:'=?',
              },
              template: (
                  '&lt;input ' +
                  'type="checkbox" ' +
                  'ng-disabled="disabled" ' +
                  'aria-checked= "false" ' +
                  'ng-value="value"/&gt;'
              ),
  
          };
      }
  
      modifiedInput.$inject = ["$window", "$rootScope", '_'];
      module.exports = modifiedInput;
  </code></pre>