[sensors] Introduce Generic Sensor API interfaces

device/sensors/mojo/sensor_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 "device/sensors/mojo/sensor_impl.h"
+
+#include "device/sensors/mojo/sensor_type_converters.h"
+#include "device/sensors/platform/platform_sensor_configuration.h"
+
+namespace device {
+namespace sensors {
+
+SensorImpl::SensorImpl(mojo::InterfaceRequest<Sensor> request,
+                       scoped_refptr<device::PlatformSensor> sensor)
+    : sensor_(sensor), binding_(this, std::move(request)) {
+  sensor_->AddClient(this);
+}
+
+SensorImpl::~SensorImpl() {
+  sensor_->RemoveClient(this);
+}
+
+void SensorImpl::SetClient(SensorClientPtr client) {
+  client_ = std::move(client);
+}
+
+void SensorImpl::Start(SensorConfigurationPtr configuration,
+                       const StartCallback& callback) {
+  Result result =
+      sensor_->StartListening(
+          this, configuration.To<device::PlatformSensorConfiguration>())
+          ? Result::SUCCESS
+          : Result::FAILURE;
+  callback.Run(result);
+}
+
+void SensorImpl::Stop(SensorConfigurationPtr configuration,
+                      const StopCallback& callback) {
+  Result result =
+      sensor_->StopListening(
+          this, configuration.To<device::PlatformSensorConfiguration>())
+          ? Result::SUCCESS
+          : Result::FAILURE;
+  callback.Run(result);
+}
+
+void SensorImpl::OnSensorReadingChanged() {
+  if (client_)
+    client_->OnSensorReadingChanged();
+}
+
+void SensorImpl::OnSensorError() {
+  if (client_)
+    client_->OnSensorError();
+}
+
+}  // namespace sensors
+}  // namespace device