Remove FixRate congestion frame type.

net/quic/quic_protocol.cc

Index: net/quic/quic_protocol.cc
diff --git a/net/quic/quic_protocol.cc b/net/quic/quic_protocol.cc
index 87c9cd91b1197b841057cd43ae2f698f51fb1c06..b9acec1243cf5af8779636289da67fefab6ddddb 100644
--- a/net/quic/quic_protocol.cc
+++ b/net/quic/quic_protocol.cc
@@ -519,11 +519,6 @@ ostream& operator<<(ostream& os,
       os << "]";
       break;
     }
-    case kFixRate: {
-      os << " bitrate_in_bytes_per_second: "
-         << congestion_frame.fix_rate.bitrate.ToBytesPerSecond();
-      break;
-    }
     case kTCP: {
       const CongestionFeedbackMessageTCP& tcp = congestion_frame.tcp;
       os << " receive_window: " << tcp.receive_window;
@@ -533,10 +528,6 @@ ostream& operator<<(ostream& os,
   return os;
 }
 
-CongestionFeedbackMessageFixRate::CongestionFeedbackMessageFixRate()
-    : bitrate(QuicBandwidth::Zero()) {
-}
-
 QuicGoAwayFrame::QuicGoAwayFrame()
     : error_code(QUIC_NO_ERROR),
       last_good_stream_id(0) {