Revert of Move //device/generic_sensor to be part of the internal implementation of the Device Service.

services/device/generic_sensor/platform_sensor_reader_linux.h

-// 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.
-
-#ifndef SERVICES_DEVICE_GENERIC_SENSOR_PLATFORM_SENSOR_READER_LINUX_H_
-#define SERVICES_DEVICE_GENERIC_SENSOR_PLATFORM_SENSOR_READER_LINUX_H_
-
-#include "base/callback.h"
-#include "base/memory/ref_counted.h"
-#include "base/memory/weak_ptr.h"
-#include "base/threading/thread_checker.h"
-
-namespace base {
-class SingleThreadTaskRunner;
-}
-
-namespace device {
-
-class PlatformSensorConfiguration;
-class PlatformSensorLinux;
-struct SensorInfoLinux;
-
-// A generic reader class that can be implemented with two different strategies:
-// polling and on trigger. All methods are not thread-safe and must be called
-// on a polling thread that allows I/O.
-class SensorReader {
- public:
-  // Creates a new instance of SensorReader. At the moment, only polling
-  // reader is supported.
-  static std::unique_ptr<SensorReader> Create(
-      const SensorInfoLinux* sensor_device,
-      base::WeakPtr<PlatformSensorLinux> sensor,
-      scoped_refptr<base::SingleThreadTaskRunner> task_runner);
-
-  virtual ~SensorReader();
-
-  // Starts fetching data based on strategy this reader has chosen.
-  // Only polling strategy is supported at the moment.
-  virtual void StartFetchingData(
-      const PlatformSensorConfiguration& configuration) = 0;
-
-  // Stops fetching data.
-  virtual void StopFetchingData() = 0;
-
- protected:
-  SensorReader(base::WeakPtr<PlatformSensorLinux> sensor,
-               scoped_refptr<base::SingleThreadTaskRunner> task_runner);
-
-  // Notifies |sensor_| about an error.
-  void NotifyReadError();
-
-  // In builds with DCHECK enabled checks that methods of this
-  // and derived classes are called on a right thread.
-  THREAD_CHECKER(thread_checker_);
-
-  // A sensor that this reader is owned by and notifies about errors and
-  // readings to.
-  base::WeakPtr<PlatformSensorLinux> sensor_;
-
-  // A task runner that is used to report about new readings and errors
-  // to a |sensor_|.
-  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
-
-  // Indicates if reading is active.
-  bool is_reading_active_;
-
-  DISALLOW_COPY_AND_ASSIGN(SensorReader);
-};
-
-}  // namespace device
-
-#endif  // SERVICES_DEVICE_GENERIC_SENSOR_PLATFORM_SENSOR_READER_LINUX_H_