Gallery2 : Drm file can be set as wallpaper

- Only DRM FL file can be set as device wallpaper. Other
  licenseable files like CD and SD can not be allow for wallpaper
  because after license expaired we can not revert wallpaper
  to default.
CRs-Fixed: 804190

Change-Id: I42f501b6a06a057765f80a6a124970bec6619e85
1 file changed