MacOS auth issue fix. (#7050)

* MacOS auth issue fix.

On MacOS 11 catalyst apps when trying to open SFSafariViewController the default browser opens and the safariViewControllerDidFinish(_ controller: SFSafariViewController) delegate method calls immediately.

* TARGET_OS_MACCATALYST usige style fixed.

* Fix elif macro issue.

* Fixed wrong file changes.

* Fix formatting.

Co-authored-by: Vahagn Gevorgyan <[email protected]>

Author: gevorgyanvahagn

FirebaseAuth/Sources/Utilities/FIRAuthURLPresenter.m

@@ -91,6 +91,12 @@ - (void)presentURL:(NSURL *)URL
   _completion = [completion copy];
   dispatch_async(dispatch_get_main_queue(), ^() {
     self->_UIDelegate = UIDelegate ?: [FIRAuthDefaultUIDelegate defaultUIDelegate];
+#if TARGET_OS_MACCATALYST
+    self->_webViewController = [[FIRAuthWebViewController alloc] initWithURL:URL delegate:self];
+    UINavigationController *navController =
+        [[UINavigationController alloc] initWithRootViewController:self->_webViewController];
+    [self->_UIDelegate presentViewController:navController animated:YES completion:nil];
+#else
     if ([SFSafariViewController class]) {
       self->_safariViewController = [[SFSafariViewController alloc] initWithURL:URL];
       self->_safariViewController.delegate = self;
@@ -104,6 +110,7 @@ - (void)presentURL:(NSURL *)URL
           [[UINavigationController alloc] initWithRootViewController:self->_webViewController];
       [self->_UIDelegate presentViewController:navController animated:YES completion:nil];
     }
+#endif
   });
 }