[Auth] Restore User decoding to pre-11 behavior (#14069)

Author: ncooke3

FirebaseAuth/CHANGELOG.md

@@ -1,3 +1,8 @@
+# Unreleased
+- [fixed] Restore pre-Firebase 11 decoding behavior to prevent users getting
+  logged out when upgrading from Firebase 8.10.0 or earlier to Firebase 11.
+  (#14011)
+
 # 11.4.0
 - [fixed] Restore Firebase 10 behavior by ignoring `nil` display names used
   during multi factor enrollment. (#13856)

FirebaseAuth/Sources/Swift/User/User.swift

@@ -1704,11 +1704,6 @@ extension User: NSSecureCoding {}
 
   public required init?(coder: NSCoder) {
     guard let userID = coder.decodeObject(of: NSString.self, forKey: kUserIDCodingKey) as? String,
-          let apiKey = coder.decodeObject(of: NSString.self, forKey: kAPIKeyCodingKey) as? String,
-          let appID = coder.decodeObject(
-            of: NSString.self,
-            forKey: kFirebaseAppIDCodingKey
-          ) as? String,
           let tokenService = coder.decodeObject(of: SecureTokenService.self,
                                                 forKey: kTokenServiceCodingKey) else {
       return nil
@@ -1746,8 +1741,17 @@ extension User: NSSecureCoding {}
     self.phoneNumber = phoneNumber
     self.metadata = metadata ?? UserMetadata(withCreationDate: nil, lastSignInDate: nil)
     self.tenantID = tenantID
-    // The `heartbeatLogger` and `appCheck` will be set later via a property update.
-    requestConfiguration = AuthRequestConfiguration(apiKey: apiKey, appID: appID)
+
+    // Note, in practice, the caller will set the `auth` property of this user
+    // instance which will as a side-effect overwrite the request configuration.
+    // The assignment here is a best-effort placeholder.
+    let apiKey = coder.decodeObject(of: NSString.self, forKey: kAPIKeyCodingKey) as? String
+    let appID = coder.decodeObject(
+      of: NSString.self,
+      forKey: kFirebaseAppIDCodingKey
+    ) as? String
+    requestConfiguration = AuthRequestConfiguration(apiKey: apiKey ?? "", appID: appID ?? "")
+
     userProfileUpdate = UserProfileUpdate()
     #if os(iOS)
       self.multiFactor = multiFactor ?? MultiFactor()