Delete PCC code.

We've not been actively experimenting with it for a while.  Deleting it will reduce maintenance cost, and we can always recover the code later.

PiperOrigin-RevId: 359536805
Change-Id: I82fa6974fde74520810c94b96cd6ea4e86c99e24

quic/core/congestion_control/send_algorithm_interface.cc

diff --git a/quic/core/congestion_control/send_algorithm_interface.cc b/quic/core/congestion_control/send_algorithm_interface.cc
index 800e844..22f164c 100644
--- a/quic/core/congestion_control/send_algorithm_interface.cc
+++ b/quic/core/congestion_control/send_algorithm_interface.cc
@@ -12,7 +12,6 @@
 #include "quic/platform/api/quic_bug_tracker.h"
 #include "quic/platform/api/quic_flag_utils.h"
 #include "quic/platform/api/quic_flags.h"
-#include "quic/platform/api/quic_pcc_sender.h"
 
 namespace quic {
 
@@ -45,7 +44,7 @@
               ? static_cast<BbrSender*>(old_send_algorithm)
               : nullptr);
     case kPCC:
-      // PCC is work has stalled, fall back to CUBIC instead.
+      // PCC is currently not supported, fall back to CUBIC instead.
       ABSL_FALLTHROUGH_INTENDED;
     case kCubicBytes:
       return new TcpCubicSenderBytes(

quic/platform/api/quic_pcc_sender.h

diff --git a/quic/platform/api/quic_pcc_sender.h b/quic/platform/api/quic_pcc_sender.h
deleted file mode 100644
index 03db5b3..0000000
--- a/quic/platform/api/quic_pcc_sender.h
+++ /dev/null
@@ -1,28 +0,0 @@
-// 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.
-
-#ifndef QUICHE_QUIC_PLATFORM_API_QUIC_PCC_SENDER_H_
-#define QUICHE_QUIC_PLATFORM_API_QUIC_PCC_SENDER_H_
-
-#include "net/quic/platform/impl/quic_pcc_sender_impl.h"
-
-namespace quic {
-
-class SendAlgorithmInterface;
-// Interface for creating a PCC SendAlgorithmInterface
-inline SendAlgorithmInterface* CreatePccSender(
-    const QuicClock* clock,
-    const RttStats* rtt_stats,
-    const QuicUnackedPacketMap* unacked_packets,
-    QuicRandom* random,
-    QuicConnectionStats* stats,
-    QuicPacketCount initial_congestion_window,
-    QuicPacketCount max_congestion_window) {
-  return CreatePccSenderImpl(clock, rtt_stats, unacked_packets, random, stats,
-                             initial_congestion_window, max_congestion_window);
-}
-
-}  // namespace quic
-
-#endif  // QUICHE_QUIC_PLATFORM_API_QUIC_PCC_SENDER_H_