title: Prevent child element from being dragged when parent is draggable
body: <p>I have the following HTML (react) setup:</p>
  
  <pre><code>&lt;div 
      onDragStart={
      (e) =&gt; { this.bound_handleDragStart.call(this, e) }}        
      draggable="true"
  &gt;
     &lt;div&gt;Stuff here&lt;/div&gt;
     &lt;div&gt;&lt;input .../&gt;&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>This setup makes the whole outer div draggable.</p>
  
  <p>However, if the drag starts on the input, I want it to be cancelled.</p>
  
  <p>I have tried adding onDragStart to the input, adding an eventListener to the input and returning false, disabling propogation on the handle drag start, and many other things, but none of them work.</p>
  
  <p>As a not, when <code>event.target</code> returns the outer div, so I cannot see a way to work out which child started the drag.</p>
  
  <p>I am sure this can be done and cannot be too difficult?</p>
  
  <p>I have thought about moving the drag to all the inner divs, but I am not sure if this will solve my problem, or create a whole new set of problems, plus I feel like this is not the right way to go</p>