title: how to get more information from firebase error?
body: <p>I have this error from firebase that says :</p>
  
  <blockquote>
    <p>An internal error has occured, print and inspect the error details from more information.</p>
  </blockquote>
  
  <p>How can I know what the error is??,</p>
  
  <p>here is my code for printing the error</p>
  
  <pre><code> let credential = FIRFacebookAuthProvider.credentialWithAccessToken(FBSDKAccessToken.currentAccessToken().tokenString)
      FIRAuth.auth()?.signInWithCredential(credential, completion: {(user, error) in
          if error != nil {
              SCLAlertView().showError("error #1", subTitle: (error?.localizedDescription)!)
              return
          }
  })
  </code></pre>