title: Type 'IterableIterator<[number, any]>' is not an array type or a string type
body: <p>I am using ionic 4 to build an app. Whereas my app is working fine on browser but when I build android platform it is giving me error for this line</p>
  
  <pre><code>for (let [index, p] of this.cart.entries())
  </code></pre>
  
  <p>My typescript version is 3.7.2</p>
  
  <p>The error is</p>
  
  <blockquote>
    <p>Type 'IterableIterator&lt;[number, any]>' is not an array type or a
    string type. Use compiler option '--downlevelIteration' to allow iterating of iterators.</p>
  </blockquote>