title: On close of popup angular mat-slide-toggle checked property is getting removed
body: <p>Checked property of <code>mat-slide-toggle</code> is getting removed after closing the popup</p>
  
  <pre><code>&lt;mat-tab *ngFor="let card of cards" &gt;
    &lt;ng-template matTabLabel&gt;
      &lt;span&gt;{{card.title}}&lt;/span&gt;                             
    &lt;/ng-template&gt;
    &lt;ul *ngFor="let car of card.default;let i=index"&gt;
      &lt;mat-slide-toggle [checked]="car.type === 'true' ? true : false" (change)="onToggle(i,$event)"&gt;
          &lt;li&gt;{{car.name}}&lt;/li&gt;
      &lt;/mat-slide-toggle&gt;
    &lt;/ul&gt;
  &lt;/mat-tab&gt;
  </code></pre>