Fix creating share visibilities
Fix creating share visibilities

Validation fails because there is no user set.

jhass/diaspora,Flaburgan/diaspora,geraspora/diaspora,Flaburgan/diaspora,jhass/diaspora,Flaburgan/diaspora,Flaburgan/diaspora,SuperTux88/diaspora,jhass/diaspora,despora/diaspora,SuperTux88/diaspora,diaspora/diaspora,despora/diaspora,despora/diaspora,jhass/diaspora,geraspora/diaspora,geraspora/diaspora,SuperTux88/diaspora,diaspora/diaspora,SuperTux88/diaspora,geraspora/diaspora,diaspora/diaspora,despora/diaspora,diaspora/diaspora