Remove obsolete QUIC disabling code.

net/quic/chromium/quic_chromium_client_session.h

Index: net/quic/chromium/quic_chromium_client_session.h
diff --git a/net/quic/chromium/quic_chromium_client_session.h b/net/quic/chromium/quic_chromium_client_session.h
index 572ed1b7c83b6c1777238bddf5799942beac6dbe..6681592d45fe82096ed662ddc49a49e605ea111d 100644
--- a/net/quic/chromium/quic_chromium_client_session.h
+++ b/net/quic/chromium/quic_chromium_client_session.h
@@ -58,18 +58,6 @@ class NET_EXPORT_PRIVATE QuicChromiumClientSession
       public QuicChromiumPacketReader::Visitor,
       public QuicChromiumPacketWriter::Delegate {
  public:
-  // Reasons to disable QUIC, that is under certain pathological
-  // connection errors.  Note: these values must be kept in sync with
-  // the corresponding values of QuicDisabledReason in:
-  // tools/metrics/histograms/histograms.xml
-  enum QuicDisabledReason {
-    QUIC_DISABLED_NOT = 0,  // default, not disabled
-    QUIC_DISABLED_PUBLIC_RESET_POST_HANDSHAKE = 1,
-    QUIC_DISABLED_TIMEOUT_WITH_OPEN_STREAMS = 2,
-    QUIC_DISABLED_BAD_PACKET_LOSS_RATE = 3,
-    QUIC_DISABLED_MAX = 4,
-  };
-
   // An interface for observing events on a session.
   class NET_EXPORT_PRIVATE Observer {
    public:
@@ -251,8 +239,6 @@ class NET_EXPORT_PRIVATE QuicChromiumClientSession
 
   const QuicServerId& server_id() const { return server_id_; }
 
-  QuicDisabledReason disabled_reason() const { return disabled_reason_; }
-
   // Attempts to migrate session when a write error is encountered.
   void MigrateSessionOnWriteError();
 
@@ -379,7 +365,6 @@ class NET_EXPORT_PRIVATE QuicChromiumClientSession
   bool going_away_;
   // True when the session receives a go away from server due to port migration.
   bool port_migration_detected_;
-  QuicDisabledReason disabled_reason_;
   TokenBindingSignatureMap token_binding_signatures_;
   // UMA histogram counters for streams pushed to this session.
   int streams_pushed_count_;