API changes to Write path Session on down for FEC protection.

net/quic/quic_connection.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // The entity that handles framing writes for a Quic client or server.
 // Each QuicSession will have a connection associated with it.
 //
 // On the server side, the Dispatcher handles the raw reads, and hands off
 // packets via ProcessUdpPacket for framing and processing.
 //
@@ skipping 212 matching lines @@
                  const QuicVersionVector& supported_versions);
   virtual ~QuicConnection();
 
   // Sets connection parameters from the supplied |config|.
   void SetFromConfig(const QuicConfig& config);
 
   // Send the data in |data| to the peer in as few packets as possible.
   // Returns a pair with the number of bytes consumed from data, and a boolean
   // indicating if the fin bit was consumed.  This does not indicate the data
   // has been sent on the wire: it may have been turned into a packet and queued
-  // if the socket was unexpectedly blocked.
+  // if the socket was unexpectedly blocked. |fec_protection| indicates if
+  // data is to be FEC protected. Note that data that is sent immediately
+  // following MUST_FEC_PROTECT data may get protected by falling within the
+  // same FEC group.
   // If |delegate| is provided, then it will be informed once ACKs have been
   // received for all the packets written in this call.
   // The |delegate| is not owned by the QuicConnection and must outlive it.
   QuicConsumedData SendStreamData(QuicStreamId id,
                                   const IOVector& data,
                                   QuicStreamOffset offset,
                                   bool fin,
+                                  FecProtection fec_protection,
                                   QuicAckNotifier::DelegateInterface* delegate);
 
   // Send a RST_STREAM frame to the peer.
   virtual void SendRstStream(QuicStreamId id,
                              QuicRstStreamErrorCode error,
                              QuicStreamOffset bytes_written);
 
   // Send a BLOCKED frame to the peer.
   virtual void SendBlocked(QuicStreamId id);
 
@@ skipping 508 matching lines @@
   // If non-empty this contains the set of versions received in a
   // version negotiation packet.
   QuicVersionVector server_supported_versions_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicConnection);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_CONNECTION_H_