Add extra logging when QuicFramer's AppendStopWaiting fails to serialize.

net/quic/quic_framer.cc

Index: net/quic/quic_framer.cc
diff --git a/net/quic/quic_framer.cc b/net/quic/quic_framer.cc
index 15f5c6eb6c4a5434867b151dbaaf6a01a095931c..48123b3dd78ec08ce20d33a023f7607f3326cdce 100644
--- a/net/quic/quic_framer.cc
+++ b/net/quic/quic_framer.cc
@@ -2497,8 +2497,10 @@ bool QuicFramer::AppendStopWaitingFrame(const QuicPacketHeader& header,
   if (least_unacked_delta >> length_shift > 0) {
     QUIC_BUG << "packet_number_length "
              << header.public_header.packet_number_length
-             << " is too small for least_unacked_delta: "
-             << least_unacked_delta;
+             << " is too small for least_unacked_delta: " << least_unacked_delta
+             << " packet_number:" << header.packet_number
+             << "least_unacked:" << frame.least_unacked

[ramant (doing other things), 2016/06/27 22:23:54]

overly nit:  "least_unacked:" -> << " least_unacked:"

[Ryan Hamilton, 2016/06/27 22:35:09]

Done. In Final. Thanks!

+             << " version:" << quic_version_;
     return false;
   }
   if (!AppendPacketSequenceNumber(header.public_header.packet_number_length,