Upgrade GSI to v5 (#751)

Author: renkelvin

FirebaseUI.podspec

@@ -121,7 +121,7 @@ Pod::Spec.new do |s|
     google.public_header_files = 'GoogleAuth/FirebaseGoogleAuthUI/*.h'
     google.source_files = 'GoogleAuth/FirebaseGoogleAuthUI/*.{h,m}'
     google.dependency 'FirebaseUI/Auth'
-    google.dependency 'GoogleSignIn', '~> 4.0'
+    google.dependency 'GoogleSignIn', '~> 5.0'
     google.resource_bundle = {
       'FirebaseGoogleAuthUI' => ['GoogleAuth/FirebaseGoogleAuthUI/**/*.{png,lproj}']
     }

GoogleAuth/FirebaseGoogleAuthUI/FUIGoogleAuth.m

@@ -43,7 +43,7 @@
  */
 static NSString *const kSignInWithGoogle = @"SignInWithGoogle";
 
-@interface FUIGoogleAuth () <GIDSignInDelegate, GIDSignInUIDelegate>
+@interface FUIGoogleAuth () <GIDSignInDelegate>
 @end
 @implementation FUIGoogleAuth {
   /** @var _presentingViewController
@@ -125,6 +125,7 @@ - (void)signInWithDefaultValue:(nullable NSString *)defaultValue
   _presentingViewController = presentingViewController;
 
   GIDSignIn *signIn = [self configuredGoogleSignIn];
+  signIn.presentingViewController = presentingViewController;
   _pendingSignInCallback = ^(FIRAuthCredential *_Nullable credential,
                              NSError *_Nullable error,
                              _Nullable FIRAuthResultCallback result,
@@ -146,7 +147,7 @@ - (void)signOut {
 
 - (BOOL)handleOpenURL:(NSURL *)URL sourceApplication:(NSString *)sourceApplication {
   GIDSignIn *signIn = [self configuredGoogleSignIn];
-  return [signIn handleURL:URL sourceApplication:sourceApplication annotation:nil];
+  return [signIn handleURL:URL];
 }
 
 - (NSString *)email {
@@ -185,16 +186,6 @@ - (void)signIn:(GIDSignIn *)signIn
   }];
 }
 
-#pragma mark - GIDSignInUIDelegate methods
-
-- (void)signIn:(GIDSignIn *)signIn presentViewController:(UIViewController *)viewController {
-  [_presentingViewController presentViewController:viewController animated:YES completion:nil];
-}
-
-- (void)signIn:(GIDSignIn *)signIn dismissViewController:(UIViewController *)viewController {
-  [_presentingViewController dismissViewControllerAnimated:YES completion:nil];
-}
-
 #pragma mark - Helpers
 
 /** @fn configuredGoogleSignIn
@@ -204,7 +195,6 @@ - (void)signIn:(GIDSignIn *)signIn dismissViewController:(UIViewController *)vie
 - (GIDSignIn *)configuredGoogleSignIn {
   GIDSignIn *signIn = [GIDSignIn sharedInstance];
   signIn.delegate = self;
-  signIn.uiDelegate = self;
   signIn.shouldFetchBasicProfile = YES;
   signIn.clientID = [[FIRApp defaultApp] options].clientID;
   signIn.scopes = _scopes;