Revert of Add ScopedTaskEnvironment::ExecutionControlMode.

base/task_scheduler/task_scheduler_impl.cc

 // 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 "base/task_scheduler/task_scheduler_impl.h"
 
 #include <utility>
 
+#include "base/memory/ptr_util.h"
 #include "base/task_scheduler/delayed_task_manager.h"
 #include "base/task_scheduler/scheduler_worker_pool_params.h"
 #include "base/task_scheduler/sequence.h"
 #include "base/task_scheduler/sequence_sort_key.h"
 #include "base/task_scheduler/task.h"
 #include "base/task_scheduler/task_tracker.h"
 
 namespace base {
 namespace internal {
 
@@ skipping 26 matching lines @@
 size_t GetEnvironmentIndexForTraits(const TaskTraits& traits) {
   const bool is_background =
       traits.priority() == base::TaskPriority::BACKGROUND;
   if (traits.may_block() || traits.with_base_sync_primitives())
     return is_background ? BACKGROUND_BLOCKING : FOREGROUND_BLOCKING;
   return is_background ? BACKGROUND : FOREGROUND;
 }
 
 }  // namespace
 
-TaskSchedulerImpl::TaskSchedulerImpl(
-    StringPiece name,
-    std::unique_ptr<TaskTrackerType> task_tracker)
+TaskSchedulerImpl::TaskSchedulerImpl(StringPiece name)
     : name_(name),
       service_thread_("TaskSchedulerServiceThread"),
-      task_tracker_(std::move(task_tracker)),
-      single_thread_task_runner_manager_(task_tracker_.get(),
+      single_thread_task_runner_manager_(&task_tracker_,
                                          &delayed_task_manager_) {
   static_assert(arraysize(worker_pools_) == ENVIRONMENT_COUNT,
                 "The size of |worker_pools_| must match ENVIRONMENT_COUNT.");
   static_assert(
       arraysize(kEnvironmentParams) == ENVIRONMENT_COUNT,
       "The size of |kEnvironmentParams| must match ENVIRONMENT_COUNT.");
 
   for (int environment_type = 0; environment_type < ENVIRONMENT_COUNT;
        ++environment_type) {
     worker_pools_[environment_type] = MakeUnique<SchedulerWorkerPoolImpl>(
         name_ + kEnvironmentParams[environment_type].name_suffix,
-        kEnvironmentParams[environment_type].priority_hint, task_tracker_.get(),
+        kEnvironmentParams[environment_type].priority_hint, &task_tracker_,
         &delayed_task_manager_);
   }
 }
 
 TaskSchedulerImpl::~TaskSchedulerImpl() {
 #if DCHECK_IS_ON()
   DCHECK(join_for_testing_returned_.IsSet());
 #endif
 }
 
 void TaskSchedulerImpl::Start(const TaskScheduler::InitParams& init_params) {
   // Start the service thread. On platforms that support it (POSIX except NaCL
   // SFI), the service thread runs a MessageLoopForIO which is used to support
   // FileDescriptorWatcher in the scope in which tasks run.
   Thread::Options service_thread_options;
   service_thread_options.message_loop_type =
 #if defined(OS_POSIX) && !defined(OS_NACL_SFI)
       MessageLoop::TYPE_IO;
 #else
       MessageLoop::TYPE_DEFAULT;
 #endif
   service_thread_options.timer_slack = TIMER_SLACK_MAXIMUM;
   CHECK(service_thread_.StartWithOptions(service_thread_options));
 
 #if defined(OS_POSIX) && !defined(OS_NACL_SFI)
   // Needs to happen after starting the service thread to get its
   // message_loop().
-  task_tracker_->set_watch_file_descriptor_message_loop(
+  task_tracker_.set_watch_file_descriptor_message_loop(
       static_cast<MessageLoopForIO*>(service_thread_.message_loop()));
 
 #if DCHECK_IS_ON()
-  task_tracker_->set_service_thread_handle(service_thread_.GetThreadHandle());
+  task_tracker_.set_service_thread_handle(service_thread_.GetThreadHandle());
 #endif  // DCHECK_IS_ON()
 #endif  // defined(OS_POSIX) && !defined(OS_NACL_SFI)
 
   // Needs to happen after starting the service thread to get its task_runner().
   delayed_task_manager_.Start(service_thread_.task_runner());
 
   single_thread_task_runner_manager_.Start();
 
   worker_pools_[BACKGROUND]->Start(init_params.background_worker_pool_params);
   worker_pools_[BACKGROUND_BLOCKING]->Start(
@@ skipping 58 matching lines @@
   return histograms;
 }
 
 int TaskSchedulerImpl::GetMaxConcurrentTasksWithTraitsDeprecated(
     const TaskTraits& traits) const {
   return GetWorkerPoolForTraits(traits)->GetMaxConcurrentTasksDeprecated();
 }
 
 void TaskSchedulerImpl::Shutdown() {
   // TODO(fdoray): Increase the priority of BACKGROUND tasks blocking shutdown.
-  task_tracker_->Shutdown();
+  task_tracker_.Shutdown();
 }
 
 void TaskSchedulerImpl::FlushForTesting() {
-  task_tracker_->Flush();
+  task_tracker_.Flush();
 }
 
 void TaskSchedulerImpl::JoinForTesting() {
 #if DCHECK_IS_ON()
   DCHECK(!join_for_testing_returned_.IsSet());
 #endif
   single_thread_task_runner_manager_.JoinForTesting();
   for (const auto& worker_pool : worker_pools_)
     worker_pool->DisallowWorkerDetachmentForTesting();
   for (const auto& worker_pool : worker_pools_)
     worker_pool->JoinForTesting();
   service_thread_.Stop();
 #if DCHECK_IS_ON()
   join_for_testing_returned_.Set();
 #endif
 }
 
 SchedulerWorkerPoolImpl* TaskSchedulerImpl::GetWorkerPoolForTraits(
     const TaskTraits& traits) const {
   return worker_pools_[GetEnvironmentIndexForTraits(traits)].get();
 }
 
 }  // namespace internal
 }  // namespace base