title: Unhandled Rejection (TypeError): can't access property "country", this.props is undefined
body: <p>i'm working on a react app</p>
  <p>when run this function by infinite scroll i'll get error</p>
  <blockquote>
  <p>Unhandled Rejection (TypeError): can't access property &quot;country&quot;,
  this.props is undefined</p>
  </blockquote>
  <pre><code>async pageUpdater() {
    let url = `https://newsapi.org/v2/top-headlines?country=${this.props.country}&amp;category=${this.props.category}&amp;apiKey=myapi&amp;page=${this.state.page}&amp;pageSize=${this.props.pageSize}`;
    this.setState({ loading: true })
    await fetch(url).then(response =&gt; response.json()).then(data =&gt; {
      this.setState({ articles: data.articles, totalResults: data.totalResults, loading: false })
    })
  }
  </code></pre>