Fix null TaskScheduler dereference introduced by codereview.chromium.org/2608093002

components/cronet/ios/cronet_environment.mm

 // Copyright 2016 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 "components/cronet/ios/cronet_environment.h"
 
 #include <utility>
 
 #include "base/at_exit.h"
 #include "base/atomicops.h"
 #include "base/command_line.h"
 #include "base/feature_list.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_file.h"
 #include "base/json/json_writer.h"
 #include "base/mac/bind_objc_block.h"
 #include "base/mac/foundation_util.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/statistics_recorder.h"
 #include "base/path_service.h"
 #include "base/single_thread_task_runner.h"
 #include "base/synchronization/waitable_event.h"
+#include "base/sys_info.h"
+#include "base/task_scheduler/task_scheduler.h"
 #include "base/threading/worker_pool.h"
 #include "components/cronet/histogram_manager.h"
 #include "components/cronet/ios/version.h"
 #include "components/prefs/json_pref_store.h"
 #include "components/prefs/pref_filter.h"
 #include "ios/net/cookies/cookie_store_ios.h"
 #include "ios/web/public/user_agent.h"
 #include "net/base/network_change_notifier.h"
 #include "net/cert/cert_verifier.h"
 #include "net/dns/host_resolver.h"
@@ skipping 75 matching lines @@
   return main_context_getter_.get();
 }
 
 // static
 void CronetEnvironment::Initialize() {
   // DCHECK_EQ([NSThread currentThread], [NSThread mainThread]);
   // This method must be called once from the main thread.
   if (!g_at_exit_)
     g_at_exit_ = new base::AtExitManager;
 
+  base::TaskScheduler::CreateAndSetSimpleTaskScheduler(
+      base::SysInfo::NumberOfProcessors());
+
   url::Initialize();
   base::CommandLine::Init(0, nullptr);
 
   // Without doing this, StatisticsRecorder::FactoryGet() leaks one histogram
   // per call after the first for a given name.
   base::StatisticsRecorder::Initialize();
 
   // Create a message loop on the UI thread.
   DCHECK(!base::MessageLoop::current());
   DCHECK(!g_main_message_loop);
@@ skipping 109 matching lines @@
   main_context_getter_ = new CronetURLRequestContextGetter(
       this, network_io_thread_->task_runner());
   base::subtle::MemoryBarrier();
   PostToNetworkThread(FROM_HERE,
                       base::Bind(&CronetEnvironment::InitializeOnNetworkThread,
                                  base::Unretained(this)));
 }
 
 CronetEnvironment::~CronetEnvironment() {
   // net::HTTPProtocolHandlerDelegate::SetInstance(nullptr);
+
+  // TODO(lilyhoughton) right now this is relying on there being
+  // only one CronetEnvironment (per process).  if (when?) that
+  // changes, so will this have to.
+  base::TaskScheduler* ts = base::TaskScheduler::GetInstance();
+  if (ts)
+    ts->Shutdown();
 }
 
 void CronetEnvironment::InitializeOnNetworkThread() {
   DCHECK(network_io_thread_->task_runner()->BelongsToCurrentThread());
   base::FeatureList::InitializeInstance(std::string(), std::string());
 
   static bool ssl_key_log_file_set = false;
   if (!ssl_key_log_file_set && !ssl_key_log_file_name_.empty()) {
     ssl_key_log_file_set = true;
     base::FilePath ssl_key_log_file;
@@ skipping 99 matching lines @@
   event->Signal();
 }
 
 std::string CronetEnvironment::getDefaultQuicUserAgentId() const {
   return base::SysNSStringToUTF8([[NSBundle mainBundle]
              objectForInfoDictionaryKey:@"CFBundleDisplayName"]) +
          " Cronet/" + CRONET_VERSION;
 }
 
 }  // namespace cronet