gfe-relnote: Deprecate unverified flag quic_bbr_one_mss_conservation false, because it increased retransmit rates and all work is now on BBRv2.

PiperOrigin-RevId: 305024637
Change-Id: I893dc3e80d18ef43928827cc0163b810244fc015

quic/core/congestion_control/bbr_sender.cc

diff --git a/quic/core/congestion_control/bbr_sender.cc b/quic/core/congestion_control/bbr_sender.cc
index 8331611..b6aee5a 100644
--- a/quic/core/congestion_control/bbr_sender.cc
+++ b/quic/core/congestion_control/bbr_sender.cc
@@ -920,16 +920,9 @@
     recovery_window_ += bytes_acked;
   }
 
-  // Sanity checks.  Ensure that we always allow to send at least an MSS or
-  // |bytes_acked| in response, whichever is larger.
+  // Always allow sending at least |bytes_acked| in response.
   recovery_window_ = std::max(
       recovery_window_, unacked_packets_->bytes_in_flight() + bytes_acked);
-  if (GetQuicReloadableFlag(quic_bbr_one_mss_conservation)) {
-    QUIC_RELOADABLE_FLAG_COUNT(quic_bbr_one_mss_conservation);
-    recovery_window_ =
-        std::max(recovery_window_,
-                 unacked_packets_->bytes_in_flight() + kMaxSegmentSize);
-  }
   recovery_window_ = std::max(min_congestion_window_, recovery_window_);
 }
 

quic/core/congestion_control/bbr_sender_test.cc

diff --git a/quic/core/congestion_control/bbr_sender_test.cc b/quic/core/congestion_control/bbr_sender_test.cc
index e07931b..f76e33c 100644
--- a/quic/core/congestion_control/bbr_sender_test.cc
+++ b/quic/core/congestion_control/bbr_sender_test.cc
@@ -341,7 +341,6 @@
 }
 
 TEST_F(BbrSenderTest, RemoveBytesLostInRecovery) {
-  SetQuicReloadableFlag(quic_bbr_one_mss_conservation, false);
   // Disable Ack Decimation on the receiver, because it can increase srtt.
   QuicConnectionPeer::SetAckMode(receiver_.connection(), AckMode::TCP_ACKING);
   CreateDefaultSetup();

quic/test_tools/simulator/quic_endpoint_test.cc

diff --git a/quic/test_tools/simulator/quic_endpoint_test.cc b/quic/test_tools/simulator/quic_endpoint_test.cc
index 0989a3b..967a9b1 100644
--- a/quic/test_tools/simulator/quic_endpoint_test.cc
+++ b/quic/test_tools/simulator/quic_endpoint_test.cc
@@ -155,8 +155,6 @@
 
 // Simulate three hosts trying to send data to a fourth one simultaneously.
 TEST_F(QuicEndpointTest, Competition) {
-  // TODO(63765788): Turn back on this flag when the issue if fixed.
-  SetQuicReloadableFlag(quic_bbr_one_mss_conservation, false);
   auto endpoint_a = std::make_unique<QuicEndpoint>(
       &simulator_, "Endpoint A", "Endpoint D (A)", Perspective::IS_CLIENT,
       test::TestConnectionId(42));