title: Pass parameters to Dart Polymer element
body: <p>The only solid example I could find for Dart Polymer doesn't use any parameters. How can I pass parameters to the template. Is it done through the constructor?</p>
  
  <p>My specific example is that I have a card element with a title, and I want to pass the title of the card as a string to the element.</p>
  
  <p>I have looked at <a href="https://stackoverflow.com/questions/18725254/passing-data-to-a-polymer-element" title="Passing data to a Polymer element">Passing data to a Polymer element</a></p>
  
  <p>but this is not exactly what I want to do. I want to pass data from within dart code.</p>