Theiry implementations were empty both for iOS (well,
TiledLibreOffice, our iOS test viewer app, anyway) and Android.  Part
of work to make TiledLibreOffice use LibreOffieKit instead of
<touch/touch.h> and the older Writer-specific tiled rendering API.

Change-Id: I602a1ebd58ec2c8d6b2d170d65e157d91e0bf521