title: Polymer 1: Reload importHref with modified content
body: <p>In Polymer 1.x I am using importHref to dynamically load some HTML content. This works fine as expected. Is there a way to reload the same import dynamically with on-the-fly changed content. In other words,</p>
  
  <ul>
  <li>Import file using importHref.</li>
  <li>A section on the UI shows the imported HTML content that can be modified.</li>
  <li>After modification, clicking on a button destroys the previous import and reloads the new content.</li>
  </ul>