http, http2: add 103 Early Hints status code

PR-URL: #16644
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>

Author: yosuke-furukawa

lib/_http_server.js

@@ -44,6 +44,7 @@ const STATUS_CODES = {
   100: 'Continue',
   101: 'Switching Protocols',
   102: 'Processing',                 // RFC 2518, obsoleted by RFC 4918
+  103: 'Early Hints',
   200: 'OK',
   201: 'Created',
   202: 'Accepted',

src/node_http2.h

@@ -158,6 +158,7 @@ HTTP_KNOWN_HEADER_MAX
   V(CONTINUE, 100)                                                            \
   V(SWITCHING_PROTOCOLS, 101)                                                 \
   V(PROCESSING, 102)                                                          \
+  V(EARLY_HINTS, 103)                                                         \
   V(OK, 200)                                                                  \
   V(CREATED, 201)                                                             \
   V(ACCEPTED, 202)                                                            \

test/parallel/test-http2-binding.js

@@ -31,6 +31,7 @@ const expectedStatusCodes = {
   HTTP_STATUS_CONTINUE: 100,
   HTTP_STATUS_SWITCHING_PROTOCOLS: 101,
   HTTP_STATUS_PROCESSING: 102,
+  HTTP_STATUS_EARLY_HINTS: 103,
   HTTP_STATUS_OK: 200,
   HTTP_STATUS_CREATED: 201,
   HTTP_STATUS_ACCEPTED: 202,