title: React Native FlatList horizontal mode not working at all
body: <p>I am using React Native 0.44.0 and I am attempting to make a horizontal FlatList using a card style layout. For whatever reason, no matter what I do, I cannot get the horizontal mode to activate. It always seems to render vertically...</p>
  
  <p>Here is the code I am using:</p>
  
  <pre><code> &lt;FlatList
      horizontal={true}
      data={this.state.newsFeed}
      refreshing={this.state.refreshing}
      ref={ref =&gt; {
          this.newsFeedListRef = ref;
      }}
      renderItem={this.renderNewsFeedRow.bind(this)}
      keyExtractor={(item, index) =&gt; `feed_${index}`}
      onRefresh={this.__handleNewsFeedOnRefresh.bind(this)}
      renderScrollComponent={this.renderScrollComponent.bind(this)}
      ListHeaderComponent={this.renderListHeaderComponent.bind(this)}
      getItemLayout={(data, index) =&gt; ({
          index,
          length: ITEM_HEIGHT,
          offset: ITEM_HEIGHT * index + headerBarHeight
      })} /&gt;;
  </code></pre>
  
  <p>I can post the code for my component renders but none of them use anything but padding and margins for style, so <code>flex</code> or <code>flexDirection</code> stuff. </p>