Enable 'First-Party-Only' cookies by default.

net/url_request/url_request_http_job.cc

Index: net/url_request/url_request_http_job.cc
diff --git a/net/url_request/url_request_http_job.cc b/net/url_request/url_request_http_job.cc
index 1a60ac4f52cb6e13fbc7bde9810114eba65787aa..59979a8461575a89339152db4cc3e782574bc93c 100644
--- a/net/url_request/url_request_http_job.cc
+++ b/net/url_request/url_request_http_job.cc
@@ -615,14 +615,7 @@ void URLRequestHttpJob::AddCookieHeaderAndStart() {
 void URLRequestHttpJob::DoLoadCookies() {
   CookieOptions options;
   options.set_include_httponly();
-
-  // TODO(mkwst): Drop this `if` once we decide whether or not to ship
-  // first-party cookies: https://crbug.com/459154
-  if (network_delegate() &&
-      network_delegate()->FirstPartyOnlyCookieExperimentEnabled())
-    options.set_first_party_url(request_->first_party_for_cookies());
-  else
-    options.set_include_first_party_only();
+  options.set_first_party_url(request_->first_party_for_cookies());
 
   request_->context()->cookie_store()->GetCookiesWithOptionsAsync(
       request_->url(), options, base::Bind(&URLRequestHttpJob::OnCookiesLoaded,