title: finishedWithAuth not called after authenticate method
body: <p>I have already set the clientID ,scope and then on button click in MyViewController ,i am calling method login from LoginCLass which works but after   [signIn authenticate] ,the delegate implementation finishedWithAuth is not getting called.I have set .h file as  </p>
  
  <pre><code>- (NSError *) login
  {
      NSLog(@"In login :%@ %@ %@",kClientId,scopes,actions);
  
      if(!kClientId|| !scopes)
      {
          NSLog(@"Either client ID Or scope is not specified!! ");
          NSError *err=[[NSError alloc]initWithDomain:@"Scope not specified" code:0 userInfo:nil];
         return err;
      }
      else
      {
          NSLog(@"Client ID and Scope are set.");
          GPPSignIn *signIn = [GPPSignIn sharedInstance];
          signIn.delegate = self;
          signIn.shouldFetchGooglePlusUser = YES;
          [signIn authenticate];
          [signIn trySilentAuthentication];
          return nil;
      }
  }
  - (void)finishedWithAuth:(GTMOAuth2Authentication *)auth error:(NSError *)error
  {
      NSLog(@"Received error %@ and auth object %@",error, auth);
  }  
  </code></pre>
  
  <p>and also in AppDelegate i am adding the code</p>
  
  <pre><code>- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation {
      return [GPPURLHandler handleURL:url
                    sourceApplication:sourceApplication
                           annotation:annotation];
  }
  </code></pre>
  
  <p>I have checked the bundle ID and  URL Types to be specified,they are set same as bundle ID from Google API access.</p>
  
  <p>These methods are in LoginClass which are used in MyViewController class.</p>
  
  <p>When i set the finishedWithAuth delegate to MyViewController ,by setting it as GPPSignInDelegate, the code runs fine.But, i want to use it from LoginClass.</p>
  
  <p>Any idea , where am i going wrong ??</p>