Don't cache FCM registration token operations. (#14355)

FirebaseMessaging/CHANGELOG.md

@@ -1,3 +1,6 @@
+# Unreleased
+- [fixed] Don't cache FCM registration token operations. (#14352).
+
 # 11.5.0
 - [fixed] Improve token-fetch failure logging with detailed error info. (#13997).
 

FirebaseMessaging/Sources/Token/FIRMessagingTokenDeleteOperation.m

@@ -77,7 +77,7 @@
         [self handleResponseWithData:data response:response error:error];
       };
 
-  NSURLSessionConfiguration *config = NSURLSessionConfiguration.defaultSessionConfiguration;
+  NSURLSessionConfiguration *config = NSURLSessionConfiguration.ephemeralSessionConfiguration;
   config.timeoutIntervalForResource = 60.0f;  // 1 minute
   NSURLSession *session = [NSURLSession sessionWithConfiguration:config];
   self.dataTask = [session dataTaskWithRequest:request completionHandler:requestHandler];

FirebaseMessaging/Sources/Token/FIRMessagingTokenFetchOperation.m

@@ -108,7 +108,7 @@ NSString *const kFIRMessagingFirebaseHeartbeatKey = @"X-firebase-client-log-type
         FIRMessaging_STRONGIFY(self);
         [self handleResponseWithData:data response:response error:error];
       };
-  NSURLSessionConfiguration *config = NSURLSessionConfiguration.defaultSessionConfiguration;
+  NSURLSessionConfiguration *config = NSURLSessionConfiguration.ephemeralSessionConfiguration;
   config.timeoutIntervalForResource = 60.0f;  // 1 minute
   NSURLSession *session = [NSURLSession sessionWithConfiguration:config];
   self.dataTask = [session dataTaskWithRequest:request completionHandler:requestHandler];