[Tizen] Screen orientation lock should not depend on sensor.

If JS client invokes the API screen.orientation.lock, the actual screen should be locked to correct orientation no matter whether the sensor is connected. The CL is to remove the logic of checking sensor connection.
The default orientation can be portrait, landscape and unlock. The current implementation works well if the application is displaying in full screen.
So far I see two separated issues need to be addressed on Tizen IVI:
1, Current implementation locks orientation no matter whether the app is in full screen or not. According to W3C spec (http://www.w3.org/TR/screen-orientation/#interaction-with-fullscreen-api), if the app is not in full screen, the orientation lock should be rejected. But current implementation does not do this check.
2, The "onchange" event is not fired after locking orientation is performed. The content / blink does not expose method to explicitly fire the "onchange" event. This issue is recorded by XWALK-2514.