improve orientation sensor with gyro data

when we do our own sensor fusion, we also export an
improved orientation sensor and hide the HAL sensor.
The fused orientation sensor is much more precise, fast
and smooth.

Change-Id: I0ea843b47ad9d12f6b22cce51f8629852d423126
diff --git a/services/sensorservice/SensorService.h b/services/sensorservice/SensorService.h
index 77a7e34..4d0f1d9 100644
--- a/services/sensorservice/SensorService.h
+++ b/services/sensorservice/SensorService.h
@@ -114,6 +114,7 @@
 
     // constants
     Vector<Sensor> mSensorList;
+    Vector<Sensor> mUserSensorList;
     DefaultKeyedVector<int, SensorInterface*> mSensorMap;
     Vector<SensorInterface *> mVirtualSensorList;
     Permission mDump;