Refetch token if attempt was invalidated (#5769)

Author: schmidt-sebastian

Firestore/CHANGELOG.md

@@ -1,4 +1,6 @@
 # Unreleased
+- [fixed] Fixed an issue that may have prevented the client from connecting
+  to the backend immediately after a user signed in.
 
 # v1.15.0
 - [changed] Internal improvements for future C++ and Unity support. Includes a

Firestore/core/src/auth/firebase_credentials_provider_apple.mm

@@ -24,6 +24,7 @@
 
 #include "Firestore/core/src/util/error_apple.h"
 #include "Firestore/core/src/util/hard_assert.h"
+#include "Firestore/core/src/util/log.h"
 #include "Firestore/core/src/util/string_apple.h"
 
 namespace firebase {
@@ -97,8 +98,8 @@
       // Cancel the request since the user changed while the request was
       // outstanding so the response is likely for a previous user (which
       // user, we can't be sure).
-      completion(util::Status(Error::kErrorAborted,
-                              "GetToken aborted due to token change."));
+      LOG_DEBUG("GetToken aborted due to token change.");
+      return GetToken(completion);
     } else {
       if (error == nil) {
         if (token != nil) {