Fix: respect "withCredentials: false" in RCTNetworking iOS (#24629)

Summary:
Fixes #24080.

Even with `withCredentials: false` network requests still sending cookies. Fix this behaviour according to https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/withCredentials.

[iOS] [Fixed] - Respect "withCredentials: false" in network requests
Pull Request resolved: #24629

Differential Revision: D15120420

Pulled By: cpojer

fbshipit-source-id: 78b9924436b02584c4fc1aa04763dff085eea78c

Author: Dmitry Dushkin

Libraries/Network/RCTNetworking.mm

@@ -259,10 +259,13 @@ - (RCTURLRequestCancellationBlock)buildRequest:(NSDictionary<NSString *, id> *)q
   NSURL *URL = [RCTConvert NSURL:query[@"url"]]; // this is marked as nullable in JS, but should not be null
   NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:URL];
   request.HTTPMethod = [RCTConvert NSString:RCTNilIfNull(query[@"method"])].uppercaseString ?: @"GET";
+  request.HTTPShouldHandleCookies = [RCTConvert BOOL:query[@"withCredentials"]];
 
-  // Load and set the cookie header.
-  NSArray<NSHTTPCookie *> *cookies = [[NSHTTPCookieStorage sharedHTTPCookieStorage] cookiesForURL:URL];
-  request.allHTTPHeaderFields = [NSHTTPCookie requestHeaderFieldsWithCookies:cookies];
+  if (request.HTTPShouldHandleCookies == YES) {
+    // Load and set the cookie header.
+    NSArray<NSHTTPCookie *> *cookies = [[NSHTTPCookieStorage sharedHTTPCookieStorage] cookiesForURL:URL];
+    request.allHTTPHeaderFields = [NSHTTPCookie requestHeaderFieldsWithCookies:cookies];
+  }
 
   // Set supplied headers.
   NSDictionary *headers = [RCTConvert NSDictionary:query[@"headers"]];
@@ -273,7 +276,6 @@ - (RCTURLRequestCancellationBlock)buildRequest:(NSDictionary<NSString *, id> *)q
   }];
 
   request.timeoutInterval = [RCTConvert NSTimeInterval:query[@"timeout"]];
-  request.HTTPShouldHandleCookies = [RCTConvert BOOL:query[@"withCredentials"]];
   NSDictionary<NSString *, id> *data = [RCTConvert NSDictionary:RCTNilIfNull(query[@"data"])];
   NSString *trackingName = data[@"trackingName"];
   if (trackingName) {