gfe-relnote: Use HandshakerDelegateInterface in QUIC handshakers. Abstract keys installation, keys discarding, default encryption level change and mark handshake complete to HandshakerDelegateInterface. Protected by gfe2_reloadable_flag_quic_use_handshaker_delegate.

The final goal is remove session pointer from handshakers.

PiperOrigin-RevId: 282826263
Change-Id: I9b379ccfcebd174df1850f7df45069d388460173
diff --git a/quic/core/quic_crypto_server_stream.h b/quic/core/quic_crypto_server_stream.h
index e66e55b..d80c495 100644
--- a/quic/core/quic_crypto_server_stream.h
+++ b/quic/core/quic_crypto_server_stream.h
@@ -98,6 +98,7 @@
     virtual bool ZeroRttAttempted() const = 0;
     virtual void SetPreviousCachedNetworkParams(
         CachedNetworkParameters cached_network_params) = 0;
+    virtual void OnPacketDecrypted(EncryptionLevel level) = 0;
 
     // NOTE: Indicating that the Expect-CT header should be sent here presents a
     // layering violation to some extent. The Expect-CT header only applies to
@@ -176,6 +177,7 @@
   const QuicCryptoNegotiatedParameters& crypto_negotiated_params()
       const override;
   CryptoMessageParser* crypto_message_parser() override;
+  void OnPacketDecrypted(EncryptionLevel level) override;
   size_t BufferSizeLimitForLevel(EncryptionLevel level) const override;
   void OnSuccessfulVersionNegotiation(
       const ParsedQuicVersion& version) override;