[sensors] [mac] Fix ambient light sensor not updating its value when closing the lid with a monitor…

device/generic_sensor/platform_sensor_ambient_light_mac.h

Index: device/generic_sensor/platform_sensor_ambient_light_mac.h
diff --git a/device/generic_sensor/platform_sensor_ambient_light_mac.h b/device/generic_sensor/platform_sensor_ambient_light_mac.h
index 32f965d3f9b1aed882a121abbbf3b5990cbfc0df..a5665a630c3b2e5f8a82687e1b07037e87b00fc6 100644
--- a/device/generic_sensor/platform_sensor_ambient_light_mac.h
+++ b/device/generic_sensor/platform_sensor_ambient_light_mac.h
@@ -56,6 +56,9 @@ class PlatformSensorAmbientLightMac : public PlatformSensor {
   base::mac::ScopedIOObject<io_object_t> light_sensor_object_;
   // IO Notifications created by IOServiceAddInterestNotification.
   base::mac::ScopedIOObject<io_object_t> light_sensor_notification_;
+  // IO Notifications created by IOServiceAddInterestNotification when the
+  // sensor is busy.
+  base::mac::ScopedIOObject<io_object_t> light_sensor_busy_notification_;
   double current_lux_;
 
   DISALLOW_COPY_AND_ASSIGN(PlatformSensorAmbientLightMac);