Make Access-Control-Request-Private-Network a forbidden header

Spec: https://wicg.github.io/private-network-access/#forbidden-header-names.

Bug: 1368527
Change-Id: Id47a68dfbd2ddafa676b6617dcdd3cc94f459f7e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4084910
Commit-Queue: Jonathan Hao <phao@chromium.org>
Reviewed-by: Finnur Thorarinsson <finnur@chromium.org>
Reviewed-by: Bence Béky <bnc@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1080897}
diff --git a/fetch/api/basic/request-forbidden-headers.any.js b/fetch/api/basic/request-forbidden-headers.any.js
index fa5e277..511ce60 100644
--- a/fetch/api/basic/request-forbidden-headers.any.js
+++ b/fetch/api/basic/request-forbidden-headers.any.js
@@ -36,6 +36,9 @@
 
 requestForbiddenHeaders("Access-Control-Request-Headers is a forbidden request header", {"Access-Control-Request-Headers": ""});
 requestForbiddenHeaders("Access-Control-Request-Method is a forbidden request header", {"Access-Control-Request-Method": ""});
+requestForbiddenHeaders(
+    'Access-Control-Request-Private-Network is a forbidden request header',
+    {'Access-Control-Request-Private-Network': ''});
 requestForbiddenHeaders("Connection is a forbidden request header", {"Connection": "close"});
 requestForbiddenHeaders("Content-Length is a forbidden request header", {"Content-Length": "42"});
 requestForbiddenHeaders("Cookie is a forbidden request header", {"Cookie": "cookie=none"});
diff --git a/fetch/api/request/request-headers.any.js b/fetch/api/request/request-headers.any.js
index cb34e5a..b73b398 100644
--- a/fetch/api/request/request-headers.any.js
+++ b/fetch/api/request/request-headers.any.js
@@ -17,6 +17,7 @@
   ["Accept-Encoding", "KO"],
   ["Access-Control-Request-Headers", "KO"],
   ["Access-Control-Request-Method", "KO"],
+  ["Access-Control-Request-Private-Network", "KO"],
   ["Connection", "KO"],
   ["Content-Length", "KO"],
   ["Cookie", "KO"],