[sensors] Introduce Generic Sensor API interfaces

device/sensors/sensor_export.h

Index: device/sensors/sensor_export.h
diff --git a/device/sensors/sensor_export.h b/device/sensors/sensor_export.h
new file mode 100644
index 0000000000000000000000000000000000000000..e09bbec5f5e0c42c471b2a8eb6738f82f9aee303
--- /dev/null
+++ b/device/sensors/sensor_export.h
@@ -0,0 +1,29 @@
+// Copyright (c) 2016 The Chromium Authors. All rights reserved.

[Reilly Grant (use Gerrit), 2016/07/27 22:07:58]

nit: We don't put "(c)" in the copyright header anymore.

[Mikhail, 2016/08/09 19:38:28]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef DEVICE_SENSORS_SENSOR_EXPORT_H_
+#define DEVICE_SENSORS_SENSOR_EXPORT_H_
+
+#if defined(COMPONENT_BUILD)
+#if defined(WIN32)
+
+#if defined(DEVICE_SENSORS_IMPLEMENTATION)
+#define DEVICE_SENSOR_EXPORT __declspec(dllexport)
+#else
+#define DEVICE_SENSOR_EXPORT __declspec(dllimport)
+#endif  // defined(DEVICE_SENSORS_IMPLEMENTATION)
+
+#else  // defined(WIN32)
+#if defined(DEVICE_SENSORS_IMPLEMENTATION)
+#define DEVICE_SENSOR_EXPORT __attribute__((visibility("default")))
+#else
+#define DEVICE_SENSOR_EXPORT
+#endif
+#endif
+
+#else  // defined(COMPONENT_BUILD)
+#define DEVICE_SENSOR_EXPORT
+#endif
+
+#endif  // DEVICE_SENSORS_SENSOR_EXPORT_H_