title: Check the render method of `Drawer Sidebar`
body: <p>I'm using React-navigation module, and I Created <code>DrawerContent</code> and I Got this Error:<br>
  <code>Check the render method of "Drawer Sidebar"</code><br>
  How Can I Fix this Error?
  <a href="https://i.stack.imgur.com/tpRYv.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/tpRYv.jpg" alt="photo"></a></p>
  
  <p><strong>Default Code is ok:</strong><br>
  <code>contentComponent: props =&gt; &lt;ScrollView&gt;&lt;DrawerItems {...props} /&gt;&lt;/ScrollView&gt;</code>   </p>
  
  <p><strong>My new Code is Not ok:</strong><br>
  <code>contentComponent: DrawerContent</code><br>
  and<br>
  <code>const DrawerContent = (props) =&gt; (&lt;ScrollView&gt;&lt;DrawerItems {...props} /&gt;&lt;/ScrollView&gt;)</code></p>
  
  <p>I opened This Issue too: (<a href="https://github.com/react-community/react-navigation/issues/2175" rel="nofollow noreferrer">https://github.com/react-community/react-navigation/issues/2175</a>)</p>