Remove btree_scheduler_fuzzer

Its implementation is incorrect (it uses exit(), and that apparently does not work for LLVM fuzzers), and its ability to find actual bugs is really limited.

PiperOrigin-RevId: 524901874

build/source_list.bzl

diff --git a/build/source_list.bzl b/build/source_list.bzl
index 6501eb8..3ddc596 100644
--- a/build/source_list.bzl
+++ b/build/source_list.bzl
@@ -1308,7 +1308,6 @@
 
 ]
 fuzzers_srcs = [
-    "common/btree_scheduler_fuzzer.cc",
     "common/structured_headers_fuzzer.cc",
     "quic/core/crypto/certificate_view_der_fuzzer.cc",
     "quic/core/crypto/certificate_view_pem_fuzzer.cc",

build/source_list.gni

diff --git a/build/source_list.gni b/build/source_list.gni
index 7d493d2..3950cd3 100644
--- a/build/source_list.gni
+++ b/build/source_list.gni
@@ -1308,7 +1308,6 @@
 
 ]
 fuzzers_srcs = [
-    "src/quiche/common/btree_scheduler_fuzzer.cc",
     "src/quiche/common/structured_headers_fuzzer.cc",
     "src/quiche/quic/core/crypto/certificate_view_der_fuzzer.cc",
     "src/quiche/quic/core/crypto/certificate_view_pem_fuzzer.cc",

build/source_list.json

diff --git a/build/source_list.json b/build/source_list.json
index 1bd8736..3e8c573 100644
--- a/build/source_list.json
+++ b/build/source_list.json
@@ -1307,7 +1307,6 @@
 
   ],
   "fuzzers_srcs": [
-    "quiche/common/btree_scheduler_fuzzer.cc",
     "quiche/common/structured_headers_fuzzer.cc",
     "quiche/quic/core/crypto/certificate_view_der_fuzzer.cc",
     "quiche/quic/core/crypto/certificate_view_pem_fuzzer.cc",

quiche/common/btree_scheduler_fuzzer.cc

diff --git a/quiche/common/btree_scheduler_fuzzer.cc b/quiche/common/btree_scheduler_fuzzer.cc
deleted file mode 100644
index eb71645..0000000
--- a/quiche/common/btree_scheduler_fuzzer.cc
+++ /dev/null
@@ -1,46 +0,0 @@
-// Copyright 2023 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.
-
-#include "quiche/common/btree_scheduler.h"
-#include "quiche/common/quiche_data_reader.h"
-
-namespace {
-uint8_t ReadUint8(quiche::QuicheDataReader& reader) {
-  uint8_t result;
-  if (!reader.ReadUInt8(&result)) {
-    exit(0);
-  }
-  return result;
-}
-}  // namespace
-
-// Simple fuzzer that attempts to drive the scheduler into an invalid state that
-// would cause a QUICHE_BUG or a crash.
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data_ptr, size_t size) {
-  quiche::BTreeScheduler<uint8_t, uint8_t> scheduler;
-  quiche::QuicheDataReader reader(reinterpret_cast<const char*>(data_ptr),
-                                  size);
-  while (!reader.IsDoneReading()) {
-    switch (ReadUint8(reader)) {
-      case 0:
-        (void)scheduler.Register(ReadUint8(reader), ReadUint8(reader));
-        break;
-      case 1:
-        (void)scheduler.Unregister(ReadUint8(reader));
-        break;
-      case 2:
-        (void)scheduler.UpdatePriority(ReadUint8(reader), ReadUint8(reader));
-        break;
-      case 3:
-        (void)scheduler.Schedule(ReadUint8(reader));
-        break;
-      case 4:
-        (void)scheduler.PopFront();
-        break;
-      default:
-        return 0;
-    }
-  }
-  return 0;
-}