[sensors][mac] Make sure to update the sensor value when initializing the sensor.
IOServiceAddInterestNotification will only notify when the hardware sensor
value changes however when calling StartSensor we need to make
sure to query the value of the sensor right away to return the correct
value to JavaScript. The reason is that after calling StartSensor
the light conditions may never change and the IOServiceAddInterestNotification
callback will never be called and we return the default 0.0 sensor value. We
can fix this by making sure to initialize the sensor value in
PlatformSensorAmbientLightMac StartSensor.
BUG=606766
Review-Url: https://chromiumcodereview.appspot.com/2417643006
Cr-Commit-Position: refs/heads/master@{#426806}
2 files changed
