title: why is ngDoCheck() being called when i have called detach() from ChangeDetectorRef?
body: <p>I was going through some articles on change detection and i was trying to enable or disable change detection using the <code>changeDetectorRef.detach()</code> and <code>changeDetectorRef.reattach()</code> . </p>
  
  <p>I also hooked the component to the <code>ngDoCheck()</code> only to find <code>ngDoCheck()</code> being called even after <code>detach()</code> . 
  What am i doing wrong ? Can someone explain why <code>ngDocheck()</code> is called ?
  I have even the <code>ChangeDetectionStartegy</code> set to <code>OnPush</code> too . 
   <a href="https://juristr.com/blog/2017/03/angular-tuning-change-detection/" rel="nofollow noreferrer">This is the article i was going through to understand change detection </a> </p>
  
  <p>I have also created an example for this : <a href="https://stackblitz.com/edit/angular-4ytdbs" rel="nofollow noreferrer">https://stackblitz.com/edit/angular-4ytdbs</a></p>