title: Using a Polymer Behavior function in a template
body: <p>I'm new to polymer and this may be an obvious question. I'm running into an issue where I can't getting an not defined function error when one of my elements is loading.</p>
  
  <p>Here is a code snippet:</p>
  
  <pre><code>   &lt;link rel='import' href='../polymer/polymer.html'&gt;
     &lt;link rel='import' href='../app-localize-behavior/app-localize-behavior.html'&gt;
     &lt;link rel='import' href='../paper-button/paper-button.html'&gt;
     &lt;dom-module id='client'&gt;
         &lt;template&gt;
            &lt;div class='buttonContainer'&gt;
               &lt;paper-button raised id='closeChat' class="green"&gt;{{localize('agent.closeChat')}}&lt;/paper-button&gt;  
            &lt;/div&gt;
         &lt;/template&gt;
         &lt;script&gt;
         Client = Polymer({
         is: "client-interface",
         behaviors: [
          Polymer.AppLocalizeBehavior
         ],
  
         // works as expected
         attached: function() {
           this.loadResources(this.resolveUrl('./locales.json'))
         },
      &lt;/script&gt;
  
   &lt;/dom-module&gt;
  </code></pre>
  
  <p>The 'localize' function is throwing an error and stops the template from loading. If I call the localize function after the 'attached' callback is fired, the localize method is available.</p>
  
  <p>What is the idiomatic way to avoid these loading issues if I'm calling a function from a behavior inside my template?</p>