[sensors] Add Generic Sensor platform unit tests.

device/generic_sensor/fake_platform_sensor.cc

Index: device/generic_sensor/fake_platform_sensor.cc
diff --git a/device/generic_sensor/fake_platform_sensor.cc b/device/generic_sensor/fake_platform_sensor.cc
new file mode 100644
index 0000000000000000000000000000000000000000..dd21afc7b17ebee2fd0dd694d014feb630487300
--- /dev/null
+++ b/device/generic_sensor/fake_platform_sensor.cc
@@ -0,0 +1,41 @@
+// 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/fake_platform_sensor.h"
+
+namespace device {
+
+FakePlatformSensor::FakePlatformSensor(mojom::SensorType type,
+                                       mojo::ScopedSharedBufferMapping mapping,
+                                       uint64_t buffer_size,
+                                       PlatformSensorProvider* provider)
+    : PlatformSensor(type, std::move(mapping), provider), started_(false) {}
+
+FakePlatformSensor::~FakePlatformSensor() = default;
+
+mojom::ReportingMode FakePlatformSensor::GetReportingMode() {
+  return mojom::ReportingMode::CONTINUOUS;
+}
+
+PlatformSensorConfiguration FakePlatformSensor::GetDefaultConfiguration() {
+  return PlatformSensorConfiguration();
+}
+
+bool FakePlatformSensor::StartSensor(
+    const PlatformSensorConfiguration& configuration) {
+  config_ = configuration;
+  started_ = true;
+  return started_;
+}
+
+void FakePlatformSensor::StopSensor() {
+  started_ = false;
+}
+
+bool FakePlatformSensor::CheckSensorConfiguration(
+    const PlatformSensorConfiguration& configuration) {
+  return configuration.frequency() <= kMaxFrequencyValueForTests;
+}
+
+}  // namespace device