[sensors] Introduce Generic Sensor API interfaces

device/generic_sensor/platform_sensor_configuration.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/generic_sensor/platform_sensor_configuration.h"
+
+namespace device {
+
+PlatformSensorConfiguration::PlatformSensorConfiguration(double frequency)
+    : frequency_(frequency) {
+  DCHECK(frequency_ <= kMaxAllowedFrequency && frequency_ > 0.0);
+}
+
+PlatformSensorConfiguration::PlatformSensorConfiguration() = default;
+PlatformSensorConfiguration::~PlatformSensorConfiguration() = default;
+
+bool PlatformSensorConfiguration::operator==(
+    const PlatformSensorConfiguration& other) const {
+  return frequency_ == other.frequency();
+}
+
+}  // namespace device