title: Displaying label when use cancel's the google sign in flow
body: <p>i'm new to iOS development and am trying to implement a google sign in in my app. I have managed to achieve the whole sign in and log out process however I am having difficulty trying to display a label if the user choses to cancel the google sign in flow instead of allowing it access. </p>
  
  <p>i believe i need to use GIDSignInErrorCode to check if the user cancelled the login but i can't seem to get it to work!</p>
  
  <p>Appdelegate.swift</p>
  
  <pre><code>func sign(_ signIn: GIDSignIn!, didSignInFor user: GIDGoogleUser!, withError error: Error!) {
      if let err = error {
          print ("Failed to log in to FitID with Google: ", err)
          return
      }
  
  
  
      print ("Successfully logged in to FitID with Google", user)
      print(user.profile.imageURL(withDimension: 400))
  </code></pre>
  
  <p>viewController.swift</p>
  
  <pre><code>IBAction func handleCustomGoogleLogin () {
  
      GIDSignIn.sharedInstance().signIn()
  
  }
  </code></pre>