Add static QUIC tag for new ORIGIN frame

This CL adds a new static QUIC tag, ORIG, which will be sent from Chromium to ask the server to send the new HTTP/3 ORIGIN frame.

PiperOrigin-RevId: 813243360

quiche/quic/core/crypto/crypto_protocol.h

diff --git a/quiche/quic/core/crypto/crypto_protocol.h b/quiche/quic/core/crypto/crypto_protocol.h
index a23c64d..d956d32 100644
--- a/quiche/quic/core/crypto/crypto_protocol.h
+++ b/quiche/quic/core/crypto/crypto_protocol.h
@@ -479,6 +479,9 @@
 DEFINE_STATIC_QUIC_TAG(NOIP);
 DEFINE_STATIC_QUIC_TAG(NIPA);  // Aggressively skip IP matching
 
+// Experiment for sending new ORIGIN frame.
+DEFINE_STATIC_QUIC_TAG(ORIG);
+
 // Rejection tags
 DEFINE_STATIC_QUIC_TAG(RREJ);  // Reasons for server sending