In quicconnection, refactor the code to calculate release time delay into a separate function. no behavior change.

PiperOrigin-RevId: 310392260
Change-Id: Ic3b63af5fa3f3bb89c75c312c1296860fa475a3a
diff --git a/quic/core/quic_packet_writer.h b/quic/core/quic_packet_writer.h
index bd10523..ab29e15 100644
--- a/quic/core/quic_packet_writer.h
+++ b/quic/core/quic_packet_writer.h
@@ -28,8 +28,10 @@
   // would not forget to override it.
   virtual std::unique_ptr<PerPacketOptions> Clone() const = 0;
 
-  // Specifies release time delay for this packet.
+  // Specifies ideal release time delay for this packet.
   QuicTime::Delta release_time_delay = QuicTime::Delta::Zero();
+  // Whether it is allowed to send this packet without |release_time_delay|.
+  bool allow_burst = false;
 };
 
 // An interface between writers and the entity managing the