Deprecate --gfe2_reloadable_flag_quic_spdy_stream_check_connected_after_process_input.

PiperOrigin-RevId: 474062830

quiche/quic/core/http/quic_spdy_stream.cc

diff --git a/quiche/quic/core/http/quic_spdy_stream.cc b/quiche/quic/core/http/quic_spdy_stream.cc
index 4951a81..bce3722 100644
--- a/quiche/quic/core/http/quic_spdy_stream.cc
+++ b/quiche/quic/core/http/quic_spdy_stream.cc
@@ -828,11 +828,7 @@
     QuicByteCount processed_bytes = decoder_.ProcessInput(
         reinterpret_cast<const char*>(iov.iov_base), iov.iov_len);
     is_decoder_processing_input_ = false;
-    if (GetQuicReloadableFlag(
-            quic_spdy_stream_check_connected_after_process_input) &&
-        !session()->connection()->connected()) {
-      QUIC_RELOADABLE_FLAG_COUNT(
-          quic_spdy_stream_check_connected_after_process_input);
+    if (!session()->connection()->connected()) {
       return;
     }
     sequencer_offset_ += processed_bytes;

quiche/quic/core/quic_flags_list.h

diff --git a/quiche/quic/core/quic_flags_list.h b/quiche/quic/core/quic_flags_list.h
index 71ee83e..8f7828c 100644
--- a/quiche/quic/core/quic_flags_list.h
+++ b/quiche/quic/core/quic_flags_list.h
@@ -27,8 +27,6 @@
 QUIC_FLAG(quic_reloadable_flag_quic_add_process_packet_context, true)
 // If true, QuicGsoBatchWriter will support release time if it is available and the process has the permission to do so.
 QUIC_FLAG(quic_restart_flag_quic_support_release_time_for_gso, false)
-// If true, QuicSpdyStream::OnDataAvailable will check if connection is still connected after HttpDecoder::ProcessInput.
-QUIC_FLAG(quic_reloadable_flag_quic_spdy_stream_check_connected_after_process_input, true)
 // If true, ack frequency frame can be sent from server to client.
 QUIC_FLAG(quic_reloadable_flag_quic_can_send_ack_frequency, true)
 // If true, allow client to enable BBRv2 on server via connection option \'B2ON\'.