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

device/generic_sensor/platform_sensor_linux.cc

Index: device/generic_sensor/platform_sensor_linux.cc
diff --git a/device/generic_sensor/platform_sensor_linux.cc b/device/generic_sensor/platform_sensor_linux.cc
new file mode 100644
index 0000000000000000000000000000000000000000..5d3e07bdeafa6b78b31c761272b70390c88b4c4f
--- /dev/null
+++ b/device/generic_sensor/platform_sensor_linux.cc
@@ -0,0 +1,96 @@
+// 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 "device/generic_sensor/platform_sensor_linux.h"
+
+#include "base/single_thread_task_runner.h"
+#include "device/generic_sensor/linux/sensor_data_linux.h"
+#include "device/generic_sensor/platform_sensor_reader_linux.h"
+
+namespace device {
+
+namespace {
+
+// Checks if at least one value has been changed.
+bool HaveValuesChanged(const SensorReading& lhs, const SensorReading& rhs) {
+  return lhs.values[0] != rhs.values[0] || lhs.values[1] != rhs.values[1] ||
+         lhs.values[2] != rhs.values[2];
+}
+
+}  // namespace
+
+PlatformSensorLinux::PlatformSensorLinux(
+    mojom::SensorType type,
+    mojo::ScopedSharedBufferMapping mapping,
+    PlatformSensorProvider* provider,
+    const SensorInfoLinux* sensor_device,
+    scoped_refptr<base::SingleThreadTaskRunner> polling_thread_task_runner)
+    : PlatformSensor(type, std::move(mapping), provider),
+      default_configuration_(
+          PlatformSensorConfiguration(sensor_device->device_frequency)),
+      reporting_mode_(sensor_device->reporting_mode),
+      polling_thread_task_runner_(std::move(polling_thread_task_runner)),
+      weak_factory_(this) {
+  sensor_reader_ = SensorReader::Create(
+      sensor_device, weak_factory_.GetWeakPtr(), task_runner_);
+}
+
+PlatformSensorLinux::~PlatformSensorLinux() {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  polling_thread_task_runner_->DeleteSoon(FROM_HERE, sensor_reader_.release());
+}
+
+mojom::ReportingMode PlatformSensorLinux::GetReportingMode() {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  return reporting_mode_;
+}
+
+void PlatformSensorLinux::UpdatePlatformSensorReading(SensorReading reading) {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  bool notifyNeeded = false;
+  if (GetReportingMode() == mojom::ReportingMode::ON_CHANGE) {
+    if (!HaveValuesChanged(reading, old_values_))
+      return;
+    notifyNeeded = true;
+  }
+  old_values_ = reading;
+  reading.timestamp = (base::TimeTicks::Now() - base::TimeTicks()).InSecondsF();
+  UpdateSensorReading(reading, notifyNeeded);
+}
+
+void PlatformSensorLinux::NotifyPlatformSensorError() {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  NotifySensorError();
+}
+
+bool PlatformSensorLinux::StartSensor(
+    const PlatformSensorConfiguration& configuration) {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  polling_thread_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&SensorReader::StartFetchingData,
+                 base::Unretained(sensor_reader_.get()), configuration));
+  return true;
+}
+
+void PlatformSensorLinux::StopSensor() {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  polling_thread_task_runner_->PostTask(
+      FROM_HERE, base::Bind(&SensorReader::StopFetchingData,
+                            base::Unretained(sensor_reader_.get())));
+}
+
+bool PlatformSensorLinux::CheckSensorConfiguration(
+    const PlatformSensorConfiguration& configuration) {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  return configuration.frequency() > 0 &&
+         configuration.frequency() <= default_configuration_.frequency();
+}
+
+PlatformSensorConfiguration PlatformSensorLinux::GetDefaultConfiguration() {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  return default_configuration_;
+}
+
+}  // namespace device