title: Set Read and Publish Permissions for same session
body: <p>Hey I'm trying to use two different type of permissions.</p>
  
  <p>I know that I cant set the permission to the LoginButton authButton  together like this:</p>
  
  <pre><code>LoginButton authButton = (LoginButton) view.findViewById(R.id.authButton);
  authButton.setReadPermissions(Arrays.asList("friends_games_activity"));
  authButton.setPublishPermissions(Arrays.asList("publish_actions"));
  </code></pre>
  
  <p>and I need to call</p>
  
  <pre><code>authButton.clearPermissions();
  </code></pre>
  
  <p>between them</p>
  
  <p>But that meen If the user for example read data
  and now need to send for example score by clicking "SEND SCORE" button
  He need to press the login button again</p>
  
  <p>Is there a way to change the Session permission Without reconnecting and pressing loggin button?</p>
  
  <p>How can I add the 2 permissions (friends_games_activity and publish_actions) without problems?</p>