title: FlatList does not pass through 0 or null into renderItem prop
body: <p>If I try to render a FlatList like so:</p>
  
  <pre><code>&lt;View&gt;
     &lt;FlatList
       numColumns={2}
       data={[1, 0, 3, null]}
       renderItem={(itemData, idx) =&gt; &lt;Text key={idx}&gt;{itemData.item}&lt;/Text&gt;}
       horizontal={false}
     /&gt;
  &lt;/View&gt;
  </code></pre>
  
  <p>The only thing returned would be <code>1</code> and <code>2</code> (except they take up space in the row/column as if the other values had rendered as well–they stack up in a column). I have no access to the <code>0</code> value or the <code>null</code> value (so I can't conditionally render something else, i.e. <code>return itemData.item || 'No Data'</code>.</p>
  
  <p>If I try this (with slightly less props):</p>
  
  <pre><code>&lt;View&gt;
      &lt;FlatList
        data={[1, 0, 3, null]}
        renderItem={(itemData, idx) =&gt; &lt;Text key={idx}&gt;{itemData.item}&lt;/Text&gt;}
      /&gt;
  &lt;/View&gt;
  </code></pre>
  
  <p>I get an error <code>Invariant Violation: No item for index 2</code>.</p>
  
  <p>Is there a solution besides looping through the data beforehand and replacing all <code>0</code>'s with a string <code>"0"</code> and all <code>null</code>s, <code>undefined</code>, empty strings etc. with a string <code>"null"</code> and conditionally rendering with that: <code>return itemData.item !== 'null' ? itemData.item || 'No Data'</code></p>