registrybackend: pass the event to the cache update
registrybackend: pass the event to the cache update

This way the registry cache has more control to specify what has
changed.

MathieuDuponchelle/glib,mzabaluev/glib,MathieuDuponchelle/glib,mzabaluev/glib,MathieuDuponchelle/glib,Distrotech/glib,johne53/MB3Glib,Distrotech/glib,MathieuDuponchelle/glib,endlessm/glib,mzabaluev/glib,mzabaluev/glib,Distrotech/glib,johne53/MB3Glib,johne53/MB3Glib,endlessm/glib,endlessm/glib,johne53/MB3Glib,endlessm/glib,MathieuDuponchelle/glib,endlessm/glib,mzabaluev/glib,johne53/MB3Glib,Distrotech/glib,johne53/MB3Glib,Distrotech/glib