title: Angular [mat-dialog-close]="false" does not work
body: <p>Is there a certain reason, why <code>[mat-dialog-close]=&quot;createFurtherCheckbox.checked ? 'false' : 'true'&quot;</code> does not work, if the value for <code>[mat-dialog-close]</code> is <code>false</code>? Within a dialog I create an object by clicking a submit button and if a certain checkbox is checked, which is questioning if I want to create another object, the dialogbox shall not close, so I can create another object (in this case a course). I want the dialog to reset and stay open, if the checkbox ist checked.</p>
  <p>Even if I try <code>[mat-dialog-close]=&quot;false&quot;</code> the dialog closes.</p>
  <p>However <code>[type]=&quot;createAnotherCheckbox.checked ? 'reset' : 'button'&quot;</code> does the 'reset'-type change correctly. (Used to reset the formControls within a form)</p>
  <p><strong>create-course-dialog.component.html</strong></p>
  <pre><code>&lt;mat-dialog-actions&gt;
      &lt;mat-checkbox #createFurtherCheckbox&gt;Create another course?&lt;/mat-checkbox&gt;
      &lt;button mat-raised-button [mat-dialog-close]=&quot;createFurtherCheckbox.checked ? 'false' : 'true'&quot; [type]=&quot;createFurtherCheckbox.checked ? 'reset' : 'button'&quot;
              (click)=&quot;Submit()&quot; [disabled]=&quot;courseForm.invalid&quot;&gt;Create course&lt;/button&gt;
      &lt;button mat-raised-button mat-dialog-close&gt;Cancel&lt;/button&gt;
  &lt;/mat-dialog-actions&gt;
  </code></pre>