[sensors] Add Generic Sensor platform unit tests.

device/generic_sensor/mock_platform_sensor.h

Index: device/generic_sensor/mock_platform_sensor.h
diff --git a/device/generic_sensor/mock_platform_sensor.h b/device/generic_sensor/mock_platform_sensor.h
new file mode 100644
index 0000000000000000000000000000000000000000..95db1503c30ee392976c058d3a9c41f279d14fe0
--- /dev/null
+++ b/device/generic_sensor/mock_platform_sensor.h
@@ -0,0 +1,48 @@
+// 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_GENERIC_SENSOR_MOCK_PLATFORM_SENSOR_H_
+#define DEVICE_GENERIC_SENSOR_MOCK_PLATFORM_SENSOR_H_
+
+#include "device/generic_sensor/platform_sensor.h"
+
+namespace device {
+
+class MockPlatformSensor : public PlatformSensor {
+ public:
+  MockPlatformSensor(mojom::SensorType type,
+                     mojo::ScopedSharedBufferMapping mapping,
+                     uint64_t buffer_size,
+                     PlatformSensorProvider* provider);
+
+  mojom::ReportingMode GetReportingMode() override;
+  PlatformSensorConfiguration GetDefaultConfiguration() override;
+
+  bool started() { return started_; }
+
+  void NotifySensorReadingChanged();

[Mikhail, 2016/09/12 08:12:43]

wouldn't 'using PlatformSensor::NotifySensorReadingChanged()' help here?

[maksims (do not use this acc), 2016/09/13 08:01:02]

I don't get it. NotifySensorReadingChanged() is protected member of
PlatformSensor. Are there other ways how to access it? I'm calling it in the
unittests with mock_sensor_->NotifySensorReadingChanged();

+  void NotifySensorError();

[Mikhail, 2016/09/12 08:12:43]

ditto

+
+  const ConfigMap& config_map() const { return config_map_; }
+
+ protected:
+  ~MockPlatformSensor() override;
+  bool StartSensor(const PlatformSensorConfiguration& configuration) override;
+  void StopSensor() override;
+  bool CheckSensorConfiguration(
+      const PlatformSensorConfiguration& configuration) override;
+
+ private:
+  static constexpr double kMaxFrequencyValue = 50.0;

[Mikhail, 2016/09/12 08:12:43]

if you want too keep is as a limit for the test, it should be renamed so that it
does not clash with the same member from PlatformSensorConfiguration.
kMaxFrequencyValueForTests or smth like that

[maksims (do not use this acc), 2016/09/13 08:01:02]

Done.

+
+  PlatformSensorConfiguration config_;
+
+  bool started_;
+
+  DISALLOW_COPY_AND_ASSIGN(MockPlatformSensor);
+};
+
+}  // namespace device
+
+#endif /* DEVICE_GENERIC_SENSOR_MOCK_PLATFORM_SENSOR_H_ */