In QUIC, send data is copied to streams rather than frames. Protected by FLAGS_quic_reloadable_flag…

net/quic/core/quic_packet_creator.h

Index: net/quic/core/quic_packet_creator.h
diff --git a/net/quic/core/quic_packet_creator.h b/net/quic/core/quic_packet_creator.h
index 57c16156e11ac2a4d337aba20fac68593c0359e0..667c659d530d65cbf738a8c61e25227a3103c766 100644
--- a/net/quic/core/quic_packet_creator.h
+++ b/net/quic/core/quic_packet_creator.h
@@ -21,6 +21,7 @@
 #include "net/quic/core/quic_iovector.h"
 #include "net/quic/core/quic_packets.h"
 #include "net/quic/core/quic_pending_retransmission.h"
+#include "net/quic/core/quic_stream_frame_data_producer.h"
 #include "net/quic/platform/api/quic_export.h"
 
 namespace net {
@@ -32,7 +33,8 @@ class QUIC_EXPORT_PRIVATE QuicPacketCreator {
  public:
   // A delegate interface for further processing serialized packet.
   class QUIC_EXPORT_PRIVATE DelegateInterface
-      : public QuicConnectionCloseDelegateInterface {
+      : public QuicConnectionCloseDelegateInterface,
+        public QuicStreamFrameDataProducer {
    public:
     ~DelegateInterface() override {}
     // Called when a packet is serialized. Delegate does not take the ownership
@@ -216,6 +218,10 @@ class QUIC_EXPORT_PRIVATE QuicPacketCreator {
 
   QuicByteCount pending_padding_bytes() const { return pending_padding_bytes_; }
 
+  void set_delegate_saves_data(bool delegate_saves_data) {
+    delegate_saves_data_ = delegate_saves_data;
+  }
+
  private:
   friend class test::QuicPacketCreatorPeer;
 
@@ -261,6 +267,11 @@ class QUIC_EXPORT_PRIVATE QuicPacketCreator {
   // packet's public header.
   bool IncludeNonceInPublicHeader();
 
+  // Returns true if |frame| starts with CHLO.
+  bool StreamFrameStartsWithChlo(QuicIOVector iov,
+                                 size_t iov_offset,
+                                 const QuicStreamFrame& frame) const;
+
   // Does not own these delegates or the framer.
   DelegateInterface* delegate_;
   DebugDelegate* debug_delegate_;
@@ -310,6 +321,10 @@ class QUIC_EXPORT_PRIVATE QuicPacketCreator {
   // bytes.
   bool needs_full_padding_;
 
+  // Indicates whether frame data is saved by delegate_. TODO(fayang): Remove
+  // this boolean when deprecating quic_reloadable_flag_quic_stream_owns_data.
+  bool delegate_saves_data_;
+
   DISALLOW_COPY_AND_ASSIGN(QuicPacketCreator);
 };