title: "Cant find variable: a" error when running React Native app
body: <p>When I run this React Native application on my Android device, I get an error on the device saying "Cant find variable: a". How would I go about fixing this? I've posted my code below.</p>
  
  <pre><code>import React, {Component} from 'react';
  import {Platform, StyleSheet, Text, View} from 'react-native';
  
  const instructions = Platform.select({
    ios: 'Press Cmd+R to reload,\n' + 'Cmd+D or shake for dev menu',
    android:
      'Double tap R on your keyboard to reload,\n' +
      'Shake or press menu button for dev menu',
  });
  
  type Props = {};
  export default class App extends Component&lt;Props&gt; {
    render() {
      return (
        &lt;View style={styles.container}&gt;
          &lt;Text style={styles.welcome}&gt;Welcome to React Native!&lt;/Text&gt;
          &lt;Text style={styles.instructions}&gt;To get started, edit App.js&lt;/Text&gt;
          &lt;Text style={styles.instructions}&gt;{instructions}&lt;/Text&gt;
        &lt;/View&gt;
      );
    }
  }
  
  const styles = StyleSheet.create({
    container: {
      flex: 1,
      justifyContent: 'center',
      alignItems: 'center',
      backgroundColor: '#F5FCFF',
    },
    welcome: {
      fontSize: 20,
      textAlign: 'center',
      margin: 10,
    },
    instructions: {
      textAlign: 'center',
      color: '#333333',
      marginBottom: 5,
    },
  });
  </code></pre>