Update cupertino_client.dart

pkgs/cupertino_http/lib/src/cupertino_client.dart

@@ -307,6 +307,13 @@ class CupertinoClient extends BaseClient {
       ..headersCommaValues = request.headers
       ..maxRedirects = request.maxRedirects;
 
+    if (profile != null && request.contentLength != null) {
+      profile.requestData.headersListValues = {
+        'Content-Length': ['${request.contentLength}'],
+        ...profile.requestData.headers!
+      };
+    }
+
     final urlRequest = MutableURLRequest.fromUrl(request.url)
       ..httpMethod = request.method;
 
@@ -315,12 +322,6 @@ class CupertinoClient extends BaseClient {
       // `httpBodyStream` requires a lot of expensive setup and data passing.
       urlRequest.httpBody = Data.fromList(request.bodyBytes);
       profile?.requestData.bodySink.add(request.bodyBytes);
-      if (profile != null) {
-        final headers =
-            Map<String, List<String>>.from(profile.requestData.headers!);
-        headers['Content-Length'] = ['${request.contentLength}'];
-        profile.requestData.headersListValues = headers;
-      }
     } else if (await _hasData(stream) case (true, final s)) {
       // If the request is supposed to be bodyless (e.g. GET requests)
       // then setting `httpBodyStream` will cause the request to fail -
@@ -331,12 +332,6 @@ class CupertinoClient extends BaseClient {
         final splitter = StreamSplitter(s);
         urlRequest.httpBodyStream = splitter.split();
         unawaited(profile.requestData.bodySink.addStream(splitter.split()));
-        if (request.contentLength != null) {
-          final headers =
-              Map<String, List<String>>.from(profile.requestData.headers!);
-          headers['Content-Length'] = ['${request.contentLength}'];
-          profile.requestData.headersListValues = headers;
-        }
       }
     }