feature #22904 [HttpFoundation] Add Request::HEADER_X_FORWARDED_AWS_E…

…LB const (nicolas-grekas)

This PR was merged into the 3.3 branch.

Discussion
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[HttpFoundation] Add Request::HEADER_X_FORWARDED_AWS_ELB const

| Q             | A
| ------------- | ---
| Branch?       | 3.3
| Bug fix?      | yes (a missing part of a 3.3 feat.)
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

See symfony/symfony-docs#7045

Commits
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9ba12b0 [HttpFoundation] Add Request::HEADER_X_FORWARDED_AWS_ELB const

src/Symfony/Component/HttpFoundation/Request.php

@@ -30,12 +30,13 @@
  */
 class Request
 {
-    const HEADER_FORWARDED = 0b00001;
-    const HEADER_X_FORWARDED_ALL = 0b11110;
-    const HEADER_X_FORWARDED_FOR = 2;
-    const HEADER_X_FORWARDED_HOST = 4;
-    const HEADER_X_FORWARDED_PROTO = 8;
-    const HEADER_X_FORWARDED_PORT = 16;
+    const HEADER_FORWARDED = 0b00001; // When using RFC 7239
+    const HEADER_X_FORWARDED_FOR = 0b00010;
+    const HEADER_X_FORWARDED_HOST = 0b00100;
+    const HEADER_X_FORWARDED_PROTO = 0b01000;
+    const HEADER_X_FORWARDED_PORT = 0b10000;
+    const HEADER_X_FORWARDED_ALL = 0b11110; // All "X-Forwarded-*" headers
+    const HEADER_X_FORWARDED_AWS_ELB = 0b11010; // AWS ELB doesn't send X-Forwarded-Host
 
     /** @deprecated since version 3.3, to be removed in 4.0 */
     const HEADER_CLIENT_IP = self::HEADER_X_FORWARDED_FOR;