Adds an alarm for sending a QUIC FEC packet.

net/quic/quic_packet_creator.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.
 //
 // Accumulates frames for the next packet until more frames no longer fit or
 // it's time to create a packet from them.  Also provides packet creation of
 // FEC packets based on previously created packets.
 
 #ifndef NET_QUIC_QUIC_PACKET_CREATOR_H_
 #define NET_QUIC_QUIC_PACKET_CREATOR_H_
@@ skipping 89 matching lines @@
   SerializedPacket ReserializeAllFrames(
       const QuicFrames& frames,
       QuicSequenceNumberLength original_length);
 
   // Returns true if there are frames pending to be serialized.
   bool HasPendingFrames() const;
 
   // Returns true if there are retransmittable frames pending to be serialized.
   bool HasPendingRetransmittableFrames() const;
 
+  // TODO(jri): Remove this method.
   // Returns whether FEC protection is currently enabled. Note: Enabled does not
   // mean that an FEC group is currently active; i.e., IsFecProtected() may
   // still return false.
   bool IsFecEnabled() const;
 
   // Returns true if subsequent packets will be FEC protected. Note: True does
   // not mean that an FEC packet is currently under construction; i.e.,
   // fec_group_.get() may still be nullptr, until MaybeStartFec() is called.
   bool IsFecProtected() const;
 
@@ skipping 95 matching lines @@
   size_t max_packets_per_fec_group() const {
       return max_packets_per_fec_group_;
   }
 
   // Sets creator's max number of packets covered by an FEC group.
   // Note: While there are no constraints on |max_packets_per_fec_group|,
   // this setter enforces a min value of kLowestMaxPacketsPerFecGroup.
   // To turn off FEC protection, use StopFecProtectingPackets().
   void set_max_packets_per_fec_group(size_t max_packets_per_fec_group);
 
+  // Returns the currently open FEC group's number. If there isn't an open FEC
+  // group, returns the last closed FEC group number. Returns 0 when FEC is
+  // disabled or no FEC group has been created yet.
+  QuicFecGroupNumber fec_group_number() { return fec_group_number_; }
+
  private:
   friend class test::QuicPacketCreatorPeer;
 
   static bool ShouldRetransmit(const QuicFrame& frame);
 
   // Updates sequence number and max packet lengths on a packet or FEC group
   // boundary.
   void MaybeUpdateLengths();
 
   // Updates lengths and also starts an FEC group if FEC protection is on and
@@ skipping 45 matching lines @@
   mutable size_t packet_size_;
   QuicFrames queued_frames_;
   scoped_ptr<RetransmittableFrames> queued_retransmittable_frames_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicPacketCreator);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_PACKET_CREATOR_H_