title: Polymer 1.0 custom element in leaflet-map not working
body: <p>can anybody explain why the following 2 snippets do not have the same effect / what am I doing wrong at the 2nd :</p>
  
  <p>Working (got the marker on the map):</p>
  
  <pre><code>&lt;dom-module id="odl-map"&gt;
  &lt;template&gt;
      &lt;leaflet-map id="innerMap" style="width:100%;height:100%;" latitude="50.92062" longitude="13.34081" zoom="10"&gt;
          &lt;leaflet-marker latitude="50.92062" longitude="13.34081"&gt;&lt;/leaflet-marker&gt;
      &lt;/leaflet-map&gt;
  &lt;/template&gt;
  &lt;script&gt;
   Polymer({
       is: "odl-map",
       ready: function() {
           L.Icon.Default.imagePath="./public/components/leaflet/dist/images";
       }
   });
  &lt;/script&gt;
  </code></pre>
  
  <p></p>
  
  <p>But if I just replace the leaflet-marker with a custom element containing the leaflet-marker it does not work :</p>
  
  <pre><code>&lt;dom-module id="contact-map-item"&gt;
  &lt;template&gt;
      &lt;leaflet-marker latitude="50.92062" longitude="13.34081"&gt;&lt;/leaflet-marker&gt;
  &lt;/template&gt;
  &lt;script&gt;
      Polymer({
          is: "contact-map-item"
      })
  &lt;/script&gt;
  &lt;/dom-module&gt;
  &lt;dom-module id="odl-map"&gt;
      &lt;template&gt;
          &lt;leaflet-map id="innerMap" style="width:100%;height:100%;" latitude="50.92062" longitude="13.34081" zoom="10"&gt;
              &lt;contact-map-item&gt;&lt;/contact-map-item&gt;
          &lt;/leaflet-map&gt;
      &lt;/template&gt;
      &lt;script&gt;
       Polymer({
           is: "odl-map",
           ready: function() {
               L.Icon.Default.imagePath="./public/components/leaflet/dist/images";
           }
       });
      &lt;/script&gt;
  &lt;/dom-module&gt;
  </code></pre>