Fixes bugs in packet size computation in the creator and in the framer

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 203 matching lines @@
 
   Options* options() {
     return &options_;
   }
 
  private:
   friend class test::QuicPacketCreatorPeer;
 
   static bool ShouldRetransmit(const QuicFrame& frame);
 
-  // Starts a new FEC group with the next serialized packet, if FEC is enabled
-  // and there is not already an FEC group open.
-  InFecGroup MaybeStartFec();
+  // Updates sequence number length on a packet or FEC group boundary.
+  // Also starts an FEC group if FEC protection is on and there is not already
+  // an FEC group open.
+  InFecGroup MaybeUpdateLengthsAndStartFec();
 
   void FillPacketHeader(QuicFecGroupNumber fec_group,
                         bool fec_flag,
                         QuicPacketHeader* header);
 
   // Allows a frame to be added without creating retransmittable frames.
   // Particularly useful for retransmits using SerializeAllFrames().
   bool AddFrame(const QuicFrame& frame, bool save_retransmittable_frames);
 
   // Adds a padding frame to the current packet only if the current packet
@@ skipping 25 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_