[sensors] Introduce Generic Sensor API interfaces

device/sensors/sensor_provider_impl.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 DEVICE_SENSORS_SENSOR_PROVIDER_IMPL_H_
+#define DEVICE_SENSORS_SENSOR_PROVIDER_IMPL_H_
+
+#include "base/macros.h"
+#include "device/sensors/public/interfaces/sensor_provider.mojom.h"
+#include "mojo/public/cpp/bindings/strong_binding.h"
+
+namespace device {
+
+class PlatformSensorProvider;
+
+namespace mojom {
+
+// Implementation of SensorProvider mojo interface.
+// Uses PlatformSensorProvider singleton to create platform specific instances
+// of PlatformSensor which are used by SensorImpl.
+class SensorProviderImpl final : public SensorProvider {
+ public:
+  static void Create(mojo::InterfaceRequest<SensorProvider> request);
+
+  ~SensorProviderImpl() override;
+
+ private:
+  explicit SensorProviderImpl(mojo::InterfaceRequest<SensorProvider> request);
+
+  // SensorProvider implementation.
+  void GetSensor(device::SensorType type,
+                 SensorRequest sensor_request,
+                 const GetSensorCallback& callback) override;
+
+  mojo::StrongBinding<SensorProvider> binding_;
+  static PlatformSensorProvider* s_provider_;
+  DISALLOW_COPY_AND_ASSIGN(SensorProviderImpl);
+};
+
+}  // namespace mojom
+}  // namespace device
+
+#endif  // DEVICE_SENSORS_SENSOR_PROVIDER_IMPL_H_