Added "451 Unavailable For Legal Reasons" to ReasonPhrases

src/Microsoft.AspNetCore.Server.Kestrel/Internal/Http/ReasonPhrases.cs

@@ -51,6 +51,7 @@ public static class ReasonPhrases
         private static readonly byte[] _bytesStatus423 = Encoding.ASCII.GetBytes("423 Locked");
         private static readonly byte[] _bytesStatus424 = Encoding.ASCII.GetBytes("424 Failed Dependency");
         private static readonly byte[] _bytesStatus426 = Encoding.ASCII.GetBytes("426 Upgrade Required");
+        private static readonly byte[] _bytesStatus451 = Encoding.ASCII.GetBytes("451 Unavailable For Legal Reasons");
         private static readonly byte[] _bytesStatus500 = Encoding.ASCII.GetBytes("500 Internal Server Error");
         private static readonly byte[] _bytesStatus501 = Encoding.ASCII.GetBytes("501 Not Implemented");
         private static readonly byte[] _bytesStatus502 = Encoding.ASCII.GetBytes("502 Bad Gateway");
@@ -153,6 +154,8 @@ public static byte[] ToStatusBytes(int statusCode, string reasonPhrase = null)
                         return _bytesStatus424;
                     case 426:
                         return _bytesStatus426;
+                    case 451:
+                        return _bytesStatus451;
                     case 500:
                         return _bytesStatus500;
                     case 501:
@@ -178,4 +181,4 @@ public static byte[] ToStatusBytes(int statusCode, string reasonPhrase = null)
             return Encoding.ASCII.GetBytes(statusCode.ToString(CultureInfo.InvariantCulture) + " " + reasonPhrase);
         }
     }
-}
+}