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

device/generic_sensor/fake_platform_sensor_provider.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 "base/memory/singleton.h"
+
+#include "device/generic_sensor/fake_platform_sensor.h"
+#include "device/generic_sensor/fake_platform_sensor_provider.h"
+
+namespace device {
+
+FakePlatformSensorProvider::FakePlatformSensorProvider() = default;
+
+FakePlatformSensorProvider::~FakePlatformSensorProvider() = default;
+
+void FakePlatformSensorProvider::CreateSensorInternal(
+    mojom::SensorType type,
+    mojo::ScopedSharedBufferMapping mapping,
+    const CreateSensorCallback& callback) {
+  scoped_refptr<FakePlatformSensor> sensor =
+      new FakePlatformSensor(type, std::move(mapping), this);
+  callback.Run(std::move(sensor));
+}
+
+}  // namespace device