core: Check options when decorating a media
core: Check options when decorating a media

When decorating a media (adding missing keys in content from browse/search
operations), make sure that the source involved in decoration gets the proper
supported options.

jasuarez/grilo,GNOME/grilo,jasuarez/grilo,grilofw/grilo,grilofw/grilo,MathieuDuponchelle/grilo,MathieuDuponchelle/grilo,kyoushuu/grilo,MathieuDuponchelle/grilo,kyoushuu/grilo,kyoushuu/grilo,GNOME/grilo,jasuarez/grilo,kyoushuu/grilo,grilofw/grilo