title: report viewer doesn't show total pages
body: <p>Why does the report viewer show "?" instead of the total pages.
  how can I force it to calculate the total pages of the report ?</p>
  
  <p><img src="https://i.stack.imgur.com/spV3E.png" alt="enter image description here"></p>
  
  <p>P.S same happens in the web component of the report viewer control.</p>