Deprecate gfe2_reloadable_flag_quic_fix_willing_and_able_to_write2.

PiperOrigin-RevId: 373409295
diff --git a/quic/core/quic_flags_list.h b/quic/core/quic_flags_list.h
index 2960924..536b868 100644
--- a/quic/core/quic_flags_list.h
+++ b/quic/core/quic_flags_list.h
@@ -45,7 +45,6 @@
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_error_on_http3_push, true)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_fix_on_stream_reset, true)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_fix_stateless_reset, false)
-QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_fix_willing_and_able_to_write2, true)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_group_path_response_and_challenge_sending_closer, false)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_h3_datagram, false)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_ignore_old_priority_update_frame, true)
diff --git a/quic/core/quic_session.cc b/quic/core/quic_session.cc
index 7146195..27c3033 100644
--- a/quic/core/quic_session.cc
+++ b/quic/core/quic_session.cc
@@ -686,11 +686,8 @@
     if (HasPendingHandshake()) {
       return true;
     }
-    if (GetQuicReloadableFlag(quic_fix_willing_and_able_to_write2)) {
-      QUIC_RELOADABLE_FLAG_COUNT(quic_fix_willing_and_able_to_write2);
-      if (!IsEncryptionEstablished()) {
-        return false;
-      }
+    if (!IsEncryptionEstablished()) {
+      return false;
     }
   }
   if (control_frame_manager_.WillingToWrite() ||