title: Parse signup doesn't authenticate the user correctly
body: <p>I encountered a very strange error when signing up a user using android 6 on a specific device.
  The signup process works perfectly and the user is registered on Parse database. The code checks and if <code>ParseUser.getCurrentUser() != null</code> then the app sends the user to the main page and this all works till here. <br />
   However, I noticed that user is not able to send any requests to the server and it all rejects in the main activity and user can't even logout. The error I receive when logging out is: <br /></p>
  
  <pre><code>com.parse.ParseRequest $ParseRequestException: This user is not allowed to add a field to _User. You can change this setting in the Data Browser.
  </code></pre>
  
  <p>It seems like the authenticated user object is not matched with the original user's token on server and that is why this user get ACL errors.<br />
  I am using Parse default signup and login functions and this has happened only on one device using android 6 so far. Any guess on what could cause this issue and how can I resolve this issue?</p>