Remove calls to SequencedWorkerPool::GetSequenceTokenForCurrentThread().

chromeos/accelerometer/accelerometer_reader.cc

 // Copyright 2014 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 "chromeos/accelerometer/accelerometer_reader.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/files/file_enumerator.h"
 #include "base/files/file_util.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/memory/singleton.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/sys_info.h"
 #include "base/task_runner.h"
 #include "base/task_runner_util.h"
 #include "base/threading/platform_thread.h"
-#include "base/threading/sequenced_worker_pool.h"
+#include "base/threading/sequenced_task_runner_handle.h"
 #include "base/threading/thread_task_runner_handle.h"
 
 namespace chromeos {
 
 namespace {
 
 // Paths to access necessary data from the accelerometer device.
 const base::FilePath::CharType kAccelerometerDevicePath[] =
     FILE_PATH_LITERAL("/dev/cros-ec-accel");
 const base::FilePath::CharType kAccelerometerIioBasePath[] =
@@ skipping 190 matching lines @@
 };
 
 AccelerometerFileReader::AccelerometerFileReader()
     : initialization_successful_(false),
       observers_(
           new base::ObserverListThreadSafe<AccelerometerReader::Observer>()) {
 }
 
 void AccelerometerFileReader::Initialize(
     scoped_refptr<base::SequencedTaskRunner> sequenced_task_runner) {
-  DCHECK(
-      base::SequencedWorkerPool::GetSequenceTokenForCurrentThread().IsValid());
+  DCHECK(base::SequencedTaskRunnerHandle::IsSet());

[fdoray, 2016/08/26 14:00:22]

I assume that the goal of this is to make sure that this method runs inside a
sequenced task? SequencedTaskRunnerHandle::IsSet() will return true from both
SequencedWorkerPool and TaskScheduler sequenced tasks, while
SequencedWorkerPool::GetSequenceTokenForCurrentThread().IsValid() only works in 
SequencedWorkerPool.

Note that even if this method runs inside a task posted to
|sequenced_task_runner|, SequencedTaskRunnerHandle::Get() might not be equal to
|sequenced_task_runner| (SequencedTaskRunnerHandle::Get() could return a wrapper
around |sequenced_task_runner|).

   task_runner_ = sequenced_task_runner;
 
   // Check for accelerometer symlink which will be created by the udev rules
   // file on detecting the device.
   if (base::IsDirectoryEmpty(base::FilePath(kAccelerometerDevicePath))) {
     if (base::SysInfo::IsRunningOnChromeOS()) {
       LOG(WARNING) << "Accelerometer device directory is empty at "
                    << kAccelerometerDevicePath;
     }
     return;
@@ skipping 78 matching lines @@
         return;
       }
     }
   }
 
   initialization_successful_ = true;
   Read();
 }
 
 void AccelerometerFileReader::Read() {
-  DCHECK(
-      base::SequencedWorkerPool::GetSequenceTokenForCurrentThread().IsValid());
+  DCHECK(base::SequencedTaskRunnerHandle::IsSet());
   ReadFileAndNotify();
   task_runner_->PostNonNestableDelayedTask(
       FROM_HERE, base::Bind(&AccelerometerFileReader::Read, this),
       base::TimeDelta::FromMilliseconds(
           AccelerometerReader::kDelayBetweenReadsMs));
 }
 
 void AccelerometerFileReader::AddObserver(
     AccelerometerReader::Observer* observer) {
   observers_->AddObserver(observer);
@@ skipping 187 matching lines @@
 }
 
 AccelerometerReader::AccelerometerReader()
     : accelerometer_file_reader_(new AccelerometerFileReader()) {
 }
 
 AccelerometerReader::~AccelerometerReader() {
 }
 
 }  // namespace chromeos