title: issue in FB logout button
body: <p>I have added a sample button for logging out from facebook in my app. but infortunately it does not seem to work as it usually work. i have even tried to implement a simple button to check but. but unfortunately it does not seem to work. any help or suggestion would be appreciated.</p>
  
  <p>Here is my code for logout:</p>
  
  <pre><code>        &lt;input type="button" value="Logout" onclick="FB.Logout();"&gt;
  
  
         fbLogout(){ 
         if(typeof FB.logout == 'function')
         { if (FB.getAuthResponse())
         { FB.logout(function(response)
         { alert("you have logged out") });  
      return; } }; 
  
       alert("you have logged out"); 
       return; 
         }
  </code></pre>
  
  <p>i am getting an error as "FB.logout() called without an access token"</p>