title: Why is Twitter session response null?
body: <p>I have a custom button for twitter login. When I authorise in twitter using this button, I get back twitterSessionResult. But the response property of this object is null. 
  How can I get twitter id and email?</p>
  
  <pre><code>    twitterButton = (FancyButton) findViewById(R.id.twitter_login_button);
      twitterButton.setOnClickListener(new View.OnClickListener() {
  
          @Override
          public void onClick(View v) {
  
  
              twitterAuthClient.authorize(WelcomeActivity.this, new com.twitter.sdk.android.core.Callback&lt;TwitterSession&gt;() {
  
                  @Override
                  public void success(Result&lt;TwitterSession&gt; twitterSessionResult) {
                      Log.w("LOG", ""+ twitterSessionResult.response); // LOG: null 
                  }
  
                  @Override
                  public void failure(TwitterException e) {
                      e.printStackTrace();
                  }
              });
  
  
          }
      });
  </code></pre>