title: React-native linking getinitialurl() works even when I don't call from external link
body: <p>I use linking for opening my app from the browser.</p>
  
  <p>When I tap the link for first in-browser my app run but incoming URL don't clear after that and <code>linking.GetInitialUrl()</code> always run with that URL.</p>
  
  <p>My schema is <code>myapp://host</code> and my URL on the web is <code>myapp://host/ok</code></p>
  
  <p>I click on my URL and <code>linking.getInitialUrl()</code> works but when next time I'm back to My screen l<code>inking.getInitialUrl()</code> return my web URL without open web page by me.</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>componentDidMount() {           
          Linking.getInitialURL().then(url =&gt; {            
             if (url) {
                alert(url)
             }
           })
           .catch(err =&gt; {
             console.error(err);
           });
             Linking.addEventListener('url',this.handleOpenURL);
      }
      
      
       componentWillUnmount() {           Linking.removeEventListener('url',this.handleOpenURL);
      }
      
      handleOpenURL = (event) =&gt; { // D
          this.linkFunc(event.url);
        }</code></pre>
  </div>
  </div>
  </p>