title: How to refer slot element from its slotted element in lit-element?
body: <p>I have a component named 'stack-item' which have a slot , its html will look like this</p>
  
  <pre><code>&lt;div&gt;
  &lt;div&gt;1&lt;div&gt;
  &lt;div class='slot-style'&gt;&lt;slot&gt;&lt;/slot&gt;&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>I have used this component like this</p>
  
  <pre><code>&lt;stack-item&gt;
     &lt;another-component&gt;&lt;/another-component&gt;
  &lt;/stack-item&gt;
  </code></pre>
  
  <p>From 'another-component' how do i get the element reference for class ='slot-style' for calculating the slot width and other properties ?</p>
  
  <p>I wrote a workaround</p>
  
  <pre><code>let slotElement =this.shadowRoot.host.parentElement.shadowRoot.querySelector('slot').parentElement;
  </code></pre>
  
  <p>but is there a clean way of achieving this?</p>