title: Checkbox not getting checked in ionic2 ios10
body: <p>I am using the following code with ionic2</p>
  
  <pre><code>&lt;ion-list&gt;
    &lt;ion-item&gt;
     &lt;ion-label&gt;Sausage&lt;/ion-label&gt;
     &lt;ion-checkbox [(ngModel)]="sausage"&gt;&lt;/ion-checkbox&gt;
    &lt;/ion-item&gt;
  &lt;/ion-list&gt;
  </code></pre>
  
  <p>But checkbox not getting checked for only IOS platform. Please help me.</p>