Deprecate FLAGS_quic_always_write_queued_retransmissions.

net/quic/quic_connection.cc

Index: net/quic/quic_connection.cc
diff --git a/net/quic/quic_connection.cc b/net/quic/quic_connection.cc
index f32b1ed31fd4ef5899cce70cb92128bcc4bc8fb2..e5bc5b16250a8000e10b0796f9f34a87cfef7401 100644
--- a/net/quic/quic_connection.cc
+++ b/net/quic/quic_connection.cc
@@ -1748,25 +1748,6 @@ bool QuicConnection::ShouldDiscardPacket(const SerializedPacket& packet) {
     return true;
   }
 
-  // TODO(fayang): Remove IsUnacked and HasRetransmittableFrames from
-  // QuicSentPacketManagerInterface when deprecating
-  // gfe2_reloadable_flag_quic_always_write_queued_retransmissions.
-  if (FLAGS_quic_always_write_queued_retransmissions) {
-    return false;
-  }
-
-  // If a retransmission has been acked before sending, don't send it.
-  // This occurs if a packet gets serialized, queued, then discarded.
-  if (packet.transmission_type != NOT_RETRANSMISSION &&
-      (!sent_packet_manager_->IsUnacked(packet.original_path_id,
-                                        packet.original_packet_number) ||
-       !sent_packet_manager_->HasRetransmittableFrames(
-           packet.original_path_id, packet.original_packet_number))) {
-    DVLOG(1) << ENDPOINT << "Dropping unacked packet: " << packet_number
-             << " A previous transmission was acked while write blocked.";
-    return true;
-  }
-
   return false;
 }