In QUIC version >= 38, enables random padding of size [1, 256]

net/quic/core/quic_connection.cc

Index: net/quic/core/quic_connection.cc
diff --git a/net/quic/core/quic_connection.cc b/net/quic/core/quic_connection.cc
index 93232b5802d302d4cafdfd764b4f6790a3dd1147..e4fbc708ae0c1b0080d9f67cba621d698ef22037 100644
--- a/net/quic/core/quic_connection.cc
+++ b/net/quic/core/quic_connection.cc
@@ -1058,9 +1058,9 @@ QuicConsumedData QuicConnection::SendStreamData(
     QuicStreamId id,
     QuicIOVector iov,
     QuicStreamOffset offset,
-    bool fin,
+    StreamSendingState state,
     QuicReferenceCountedPointer<QuicAckListenerInterface> ack_listener) {
-  if (!fin && iov.total_length == 0) {
+  if (state == NO_FIN && iov.total_length == 0) {
     QUIC_BUG << "Attempt to send empty stream frame";
     return QuicConsumedData(0, false);
   }
@@ -1075,12 +1075,12 @@ QuicConsumedData QuicConnection::SendStreamData(
   // The optimized path may be used for data only packets which fit into a
   // standard buffer and don't need padding.
   if (id != kCryptoStreamId && !packet_generator_.HasQueuedFrames() &&
-      iov.total_length > kMaxPacketSize) {
+      iov.total_length > kMaxPacketSize && state != FIN_AND_PADDING) {
     // Use the fast path to send full data packets.
-    return packet_generator_.ConsumeDataFastPath(id, iov, offset, fin,
-                                                 std::move(ack_listener));
+    return packet_generator_.ConsumeDataFastPath(
+        id, iov, offset, state != NO_FIN, std::move(ack_listener));
   }
-  return packet_generator_.ConsumeData(id, iov, offset, fin ? FIN : NO_FIN,
+  return packet_generator_.ConsumeData(id, iov, offset, state,
                                        std::move(ack_listener));
 }